[FFmpeg-cvslog] Merge commit '40aaa8dadfd1c69ff4460d04750e1403b5535a6d'

Clément Bœsch git at videolan.org
Wed Mar 29 14:29:49 EEST 2017


ffmpeg | branch: master | Clément Bœsch <u at pkh.me> | Wed Mar 29 13:29:00 2017 +0200| [b785af48687fa839fbc25045d2201335753304b3] | committer: Clément Bœsch

Merge commit '40aaa8dadfd1c69ff4460d04750e1403b5535a6d'

* commit '40aaa8dadfd1c69ff4460d04750e1403b5535a6d':
  examples/avcodec: split audio encoding into a separate example

Merged-by: Clément Bœsch <u at pkh.me>

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=b785af48687fa839fbc25045d2201335753304b3
---

 configure                        |   2 +
 doc/Makefile                     |   1 +
 doc/examples/.gitignore          |   1 +
 doc/examples/Makefile            |   3 +-
 doc/examples/decoding_encoding.c | 192 --------------------------------
 doc/examples/encode_audio.c      | 235 +++++++++++++++++++++++++++++++++++++++
 6 files changed, 241 insertions(+), 193 deletions(-)

diff --git a/configure b/configure
index a84b126..bf1d2fe 100755
--- a/configure
+++ b/configure
@@ -1463,6 +1463,7 @@ EXAMPLE_LIST="
     avio_reading_example
     decoding_encoding_example
     demuxing_decoding_example
+    encode_audio_example
     extract_mvs_example
     filter_audio_example
     filtering_audio_example
@@ -3169,6 +3170,7 @@ avio_dir_cmd_deps="avformat avutil"
 avio_reading_deps="avformat avcodec avutil"
 decoding_encoding_example_deps="avcodec avformat avutil"
 demuxing_decoding_example_deps="avcodec avformat avutil"
+encode_audio_example_deps="avcodec avutil"
 extract_mvs_example_deps="avcodec avformat avutil"
 filter_audio_example_deps="avfilter avutil"
 filtering_audio_example_deps="avfilter avcodec avformat avutil"
diff --git a/doc/Makefile b/doc/Makefile
index a180fbe..396d9e0 100644
--- a/doc/Makefile
+++ b/doc/Makefile
@@ -40,6 +40,7 @@ DOC_EXAMPLES-$(CONFIG_AVIO_DIR_CMD_EXAMPLE)      += avio_dir_cmd
 DOC_EXAMPLES-$(CONFIG_AVIO_READING_EXAMPLE)      += avio_reading
 DOC_EXAMPLES-$(CONFIG_DECODING_ENCODING_EXAMPLE) += decoding_encoding
 DOC_EXAMPLES-$(CONFIG_DEMUXING_DECODING_EXAMPLE) += demuxing_decoding
+DOC_EXAMPLES-$(CONFIG_ENCODE_AUDIO_EXAMPLE)      += encode_audio
 DOC_EXAMPLES-$(CONFIG_EXTRACT_MVS_EXAMPLE)       += extract_mvs
 DOC_EXAMPLES-$(CONFIG_FILTER_AUDIO_EXAMPLE)      += filter_audio
 DOC_EXAMPLES-$(CONFIG_FILTERING_AUDIO_EXAMPLE)   += filtering_audio
diff --git a/doc/examples/.gitignore b/doc/examples/.gitignore
index 430d3bf..1a6209b 100644
--- a/doc/examples/.gitignore
+++ b/doc/examples/.gitignore
@@ -2,6 +2,7 @@
 /avio_reading
 /decoding_encoding
 /demuxing_decoding
+/encode_audio
 /extract_mvs
 /filter_audio
 /filtering_audio
diff --git a/doc/examples/Makefile b/doc/examples/Makefile
index af38159..f76e5a2 100644
--- a/doc/examples/Makefile
+++ b/doc/examples/Makefile
@@ -15,6 +15,7 @@ EXAMPLES=       avio_dir_cmd                       \
                 avio_reading                       \
                 decoding_encoding                  \
                 demuxing_decoding                  \
+                encode_audio                       \
                 extract_mvs                        \
                 filtering_video                    \
                 filtering_audio                    \
@@ -31,7 +32,7 @@ OBJS=$(addsuffix .o,$(EXAMPLES))
 
 # the following examples make explicit use of the math library
 avcodec:           LDLIBS += -lm
-decoding_encoding: LDLIBS += -lm
+encode_audio:      LDLIBS += -lm
 muxing:            LDLIBS += -lm
 resampling_audio:  LDLIBS += -lm
 
diff --git a/doc/examples/decoding_encoding.c b/doc/examples/decoding_encoding.c
index 1c5a78a..f863bdf 100644
--- a/doc/examples/decoding_encoding.c
+++ b/doc/examples/decoding_encoding.c
@@ -44,197 +44,6 @@
 #define AUDIO_INBUF_SIZE 20480
 #define AUDIO_REFILL_THRESH 4096
 
-/* check that a given sample format is supported by the encoder */
-static int check_sample_fmt(AVCodec *codec, enum AVSampleFormat sample_fmt)
-{
-    const enum AVSampleFormat *p = codec->sample_fmts;
-
-    while (*p != AV_SAMPLE_FMT_NONE) {
-        if (*p == sample_fmt)
-            return 1;
-        p++;
-    }
-    return 0;
-}
-
-/* just pick the highest supported samplerate */
-static int select_sample_rate(AVCodec *codec)
-{
-    const int *p;
-    int best_samplerate = 0;
-
-    if (!codec->supported_samplerates)
-        return 44100;
-
-    p = codec->supported_samplerates;
-    while (*p) {
-        best_samplerate = FFMAX(*p, best_samplerate);
-        p++;
-    }
-    return best_samplerate;
-}
-
-/* select layout with the highest channel count */
-static int select_channel_layout(AVCodec *codec)
-{
-    const uint64_t *p;
-    uint64_t best_ch_layout = 0;
-    int best_nb_channels   = 0;
-
-    if (!codec->channel_layouts)
-        return AV_CH_LAYOUT_STEREO;
-
-    p = codec->channel_layouts;
-    while (*p) {
-        int nb_channels = av_get_channel_layout_nb_channels(*p);
-
-        if (nb_channels > best_nb_channels) {
-            best_ch_layout    = *p;
-            best_nb_channels = nb_channels;
-        }
-        p++;
-    }
-    return best_ch_layout;
-}
-
-/*
- * Audio encoding example
- */
-static void audio_encode_example(const char *filename)
-{
-    AVCodec *codec;
-    AVCodecContext *c= NULL;
-    AVFrame *frame;
-    AVPacket pkt;
-    int i, j, k, ret, got_output;
-    int buffer_size;
-    FILE *f;
-    uint16_t *samples;
-    float t, tincr;
-
-    printf("Encode audio file %s\n", filename);
-
-    /* find the MP2 encoder */
-    codec = avcodec_find_encoder(AV_CODEC_ID_MP2);
-    if (!codec) {
-        fprintf(stderr, "Codec not found\n");
-        exit(1);
-    }
-
-    c = avcodec_alloc_context3(codec);
-    if (!c) {
-        fprintf(stderr, "Could not allocate audio codec context\n");
-        exit(1);
-    }
-
-    /* put sample parameters */
-    c->bit_rate = 64000;
-
-    /* check that the encoder supports s16 pcm input */
-    c->sample_fmt = AV_SAMPLE_FMT_S16;
-    if (!check_sample_fmt(codec, c->sample_fmt)) {
-        fprintf(stderr, "Encoder does not support sample format %s",
-                av_get_sample_fmt_name(c->sample_fmt));
-        exit(1);
-    }
-
-    /* select other audio parameters supported by the encoder */
-    c->sample_rate    = select_sample_rate(codec);
-    c->channel_layout = select_channel_layout(codec);
-    c->channels       = av_get_channel_layout_nb_channels(c->channel_layout);
-
-    /* open it */
-    if (avcodec_open2(c, codec, NULL) < 0) {
-        fprintf(stderr, "Could not open codec\n");
-        exit(1);
-    }
-
-    f = fopen(filename, "wb");
-    if (!f) {
-        fprintf(stderr, "Could not open %s\n", filename);
-        exit(1);
-    }
-
-    /* frame containing input raw audio */
-    frame = av_frame_alloc();
-    if (!frame) {
-        fprintf(stderr, "Could not allocate audio frame\n");
-        exit(1);
-    }
-
-    frame->nb_samples     = c->frame_size;
-    frame->format         = c->sample_fmt;
-    frame->channel_layout = c->channel_layout;
-
-    /* the codec gives us the frame size, in samples,
-     * we calculate the size of the samples buffer in bytes */
-    buffer_size = av_samples_get_buffer_size(NULL, c->channels, c->frame_size,
-                                             c->sample_fmt, 0);
-    if (buffer_size < 0) {
-        fprintf(stderr, "Could not get sample buffer size\n");
-        exit(1);
-    }
-    samples = av_malloc(buffer_size);
-    if (!samples) {
-        fprintf(stderr, "Could not allocate %d bytes for samples buffer\n",
-                buffer_size);
-        exit(1);
-    }
-    /* setup the data pointers in the AVFrame */
-    ret = avcodec_fill_audio_frame(frame, c->channels, c->sample_fmt,
-                                   (const uint8_t*)samples, buffer_size, 0);
-    if (ret < 0) {
-        fprintf(stderr, "Could not setup audio frame\n");
-        exit(1);
-    }
-
-    /* encode a single tone sound */
-    t = 0;
-    tincr = 2 * M_PI * 440.0 / c->sample_rate;
-    for (i = 0; i < 200; i++) {
-        av_init_packet(&pkt);
-        pkt.data = NULL; // packet data will be allocated by the encoder
-        pkt.size = 0;
-
-        for (j = 0; j < c->frame_size; j++) {
-            samples[2*j] = (int)(sin(t) * 10000);
-
-            for (k = 1; k < c->channels; k++)
-                samples[2*j + k] = samples[2*j];
-            t += tincr;
-        }
-        /* encode the samples */
-        ret = avcodec_encode_audio2(c, &pkt, frame, &got_output);
-        if (ret < 0) {
-            fprintf(stderr, "Error encoding audio frame\n");
-            exit(1);
-        }
-        if (got_output) {
-            fwrite(pkt.data, 1, pkt.size, f);
-            av_packet_unref(&pkt);
-        }
-    }
-
-    /* get the delayed frames */
-    for (got_output = 1; got_output; i++) {
-        ret = avcodec_encode_audio2(c, &pkt, NULL, &got_output);
-        if (ret < 0) {
-            fprintf(stderr, "Error encoding frame\n");
-            exit(1);
-        }
-
-        if (got_output) {
-            fwrite(pkt.data, 1, pkt.size, f);
-            av_packet_unref(&pkt);
-        }
-    }
-    fclose(f);
-
-    av_freep(&samples);
-    av_frame_free(&frame);
-    avcodec_free_context(&c);
-}
-
 /*
  * Audio decoding.
  */
@@ -646,7 +455,6 @@ int main(int argc, char **argv)
     if (!strcmp(output_type, "h264")) {
         video_encode_example("test.h264", AV_CODEC_ID_H264);
     } else if (!strcmp(output_type, "mp2")) {
-        audio_encode_example("test.mp2");
         audio_decode_example("test.pcm", "test.mp2");
     } else if (!strcmp(output_type, "mpg")) {
         video_encode_example("test.mpg", AV_CODEC_ID_MPEG1VIDEO);
diff --git a/doc/examples/encode_audio.c b/doc/examples/encode_audio.c
new file mode 100644
index 0000000..5932521
--- /dev/null
+++ b/doc/examples/encode_audio.c
@@ -0,0 +1,235 @@
+/*
+ * Copyright (c) 2001 Fabrice Bellard
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+/**
+ * @file
+ * audio encoding with libavcodec API example.
+ *
+ * @example encode_audio.c
+ */
+
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+
+#include "libavcodec/avcodec.h"
+
+#include "libavutil/channel_layout.h"
+#include "libavutil/common.h"
+#include "libavutil/frame.h"
+#include "libavutil/samplefmt.h"
+
+/* check that a given sample format is supported by the encoder */
+static int check_sample_fmt(AVCodec *codec, enum AVSampleFormat sample_fmt)
+{
+    const enum AVSampleFormat *p = codec->sample_fmts;
+
+    while (*p != AV_SAMPLE_FMT_NONE) {
+        if (*p == sample_fmt)
+            return 1;
+        p++;
+    }
+    return 0;
+}
+
+/* just pick the highest supported samplerate */
+static int select_sample_rate(AVCodec *codec)
+{
+    const int *p;
+    int best_samplerate = 0;
+
+    if (!codec->supported_samplerates)
+        return 44100;
+
+    p = codec->supported_samplerates;
+    while (*p) {
+        best_samplerate = FFMAX(*p, best_samplerate);
+        p++;
+    }
+    return best_samplerate;
+}
+
+/* select layout with the highest channel count */
+static int select_channel_layout(AVCodec *codec)
+{
+    const uint64_t *p;
+    uint64_t best_ch_layout = 0;
+    int best_nb_channels   = 0;
+
+    if (!codec->channel_layouts)
+        return AV_CH_LAYOUT_STEREO;
+
+    p = codec->channel_layouts;
+    while (*p) {
+        int nb_channels = av_get_channel_layout_nb_channels(*p);
+
+        if (nb_channels > best_nb_channels) {
+            best_ch_layout    = *p;
+            best_nb_channels = nb_channels;
+        }
+        p++;
+    }
+    return best_ch_layout;
+}
+
+int main(int argc, char **argv)
+{
+    const char *filename;
+    AVCodec *codec;
+    AVCodecContext *c= NULL;
+    AVFrame *frame;
+    AVPacket pkt;
+    int i, j, k, ret, got_output;
+    int buffer_size;
+    FILE *f;
+    uint16_t *samples;
+    float t, tincr;
+
+    if (argc <= 1) {
+        fprintf(stderr, "Usage: %s <output file>\n", argv[0]);
+        return 0;
+    }
+    filename = argv[1];
+
+    /* register all the codecs */
+    avcodec_register_all();
+
+    /* find the MP2 encoder */
+    codec = avcodec_find_encoder(AV_CODEC_ID_MP2);
+    if (!codec) {
+        fprintf(stderr, "Codec not found\n");
+        exit(1);
+    }
+
+    c = avcodec_alloc_context3(codec);
+    if (!c) {
+        fprintf(stderr, "Could not allocate audio codec context\n");
+        exit(1);
+    }
+
+    /* put sample parameters */
+    c->bit_rate = 64000;
+
+    /* check that the encoder supports s16 pcm input */
+    c->sample_fmt = AV_SAMPLE_FMT_S16;
+    if (!check_sample_fmt(codec, c->sample_fmt)) {
+        fprintf(stderr, "Encoder does not support sample format %s",
+                av_get_sample_fmt_name(c->sample_fmt));
+        exit(1);
+    }
+
+    /* select other audio parameters supported by the encoder */
+    c->sample_rate    = select_sample_rate(codec);
+    c->channel_layout = select_channel_layout(codec);
+    c->channels       = av_get_channel_layout_nb_channels(c->channel_layout);
+
+    /* open it */
+    if (avcodec_open2(c, codec, NULL) < 0) {
+        fprintf(stderr, "Could not open codec\n");
+        exit(1);
+    }
+
+    f = fopen(filename, "wb");
+    if (!f) {
+        fprintf(stderr, "Could not open %s\n", filename);
+        exit(1);
+    }
+
+    /* frame containing input raw audio */
+    frame = av_frame_alloc();
+    if (!frame) {
+        fprintf(stderr, "Could not allocate audio frame\n");
+        exit(1);
+    }
+
+    frame->nb_samples     = c->frame_size;
+    frame->format         = c->sample_fmt;
+    frame->channel_layout = c->channel_layout;
+
+    /* the codec gives us the frame size, in samples,
+     * we calculate the size of the samples buffer in bytes */
+    buffer_size = av_samples_get_buffer_size(NULL, c->channels, c->frame_size,
+                                             c->sample_fmt, 0);
+    if (buffer_size < 0) {
+        fprintf(stderr, "Could not get sample buffer size\n");
+        exit(1);
+    }
+    samples = av_malloc(buffer_size);
+    if (!samples) {
+        fprintf(stderr, "Could not allocate %d bytes for samples buffer\n",
+                buffer_size);
+        exit(1);
+    }
+    /* setup the data pointers in the AVFrame */
+    ret = avcodec_fill_audio_frame(frame, c->channels, c->sample_fmt,
+                                   (const uint8_t*)samples, buffer_size, 0);
+    if (ret < 0) {
+        fprintf(stderr, "Could not setup audio frame\n");
+        exit(1);
+    }
+
+    /* encode a single tone sound */
+    t = 0;
+    tincr = 2 * M_PI * 440.0 / c->sample_rate;
+    for (i = 0; i < 200; i++) {
+        av_init_packet(&pkt);
+        pkt.data = NULL; // packet data will be allocated by the encoder
+        pkt.size = 0;
+
+        for (j = 0; j < c->frame_size; j++) {
+            samples[2*j] = (int)(sin(t) * 10000);
+
+            for (k = 1; k < c->channels; k++)
+                samples[2*j + k] = samples[2*j];
+            t += tincr;
+        }
+        /* encode the samples */
+        ret = avcodec_encode_audio2(c, &pkt, frame, &got_output);
+        if (ret < 0) {
+            fprintf(stderr, "Error encoding audio frame\n");
+            exit(1);
+        }
+        if (got_output) {
+            fwrite(pkt.data, 1, pkt.size, f);
+            av_packet_unref(&pkt);
+        }
+    }
+
+    /* get the delayed frames */
+    for (got_output = 1; got_output; i++) {
+        ret = avcodec_encode_audio2(c, &pkt, NULL, &got_output);
+        if (ret < 0) {
+            fprintf(stderr, "Error encoding frame\n");
+            exit(1);
+        }
+
+        if (got_output) {
+            fwrite(pkt.data, 1, pkt.size, f);
+            av_packet_unref(&pkt);
+        }
+    }
+    fclose(f);
+
+    av_freep(&samples);
+    av_frame_free(&frame);
+    avcodec_free_context(&c);
+}


======================================================================

diff --cc configure
index a84b126,28567bb..bf1d2fe
--- a/configure
+++ b/configure
@@@ -1459,38 -1209,30 +1459,39 @@@ COMPONENT_LIST=
  "
  
  EXAMPLE_LIST="
 -    avcodec_example
 +    avio_dir_cmd_example
 +    avio_reading_example
 +    decoding_encoding_example
 +    demuxing_decoding_example
+     encode_audio_example
 +    extract_mvs_example
      filter_audio_example
 +    filtering_audio_example
 +    filtering_video_example
 +    http_multiclient_example
      metadata_example
 -    output_example
 +    muxing_example
      qsvdec_example
 +    remuxing_example
 +    resampling_audio_example
 +    scaling_video_example
      transcode_aac_example
 +    transcoding_example
  "
 -
 -HWACCEL_LIBRARY_NONFREE_LIST="
 -    cuda
 -    libnpp
 -"
 -HWACCEL_LIBRARY_LIST="
 -    $HWACCEL_LIBRARY_NONFREE_LIST
 -    d3d11va
 -    dxva2
 -    libmfx
 -    mmal
 -    nvenc
 -    omx
 -    vaapi
 -    vda
 -    vdpau
 +EXTERNAL_AUTODETECT_LIBRARY_LIST="
 +    bzlib
 +    iconv
 +    libxcb
 +    libxcb_shm
 +    libxcb_shape
 +    libxcb_xfixes
 +    lzma
 +    schannel
 +    sdl
 +    sdl2
 +    securetransport
 +    xlib
 +    zlib
  "
  
  EXTERNAL_LIBRARY_GPL_LIST="
@@@ -3165,23 -2435,13 +3166,24 @@@ zscale_filter_deps="libzimg
  scale_vaapi_filter_deps="vaapi VAProcPipelineParameterBuffer"
  
  # examples
 -avcodec_example_deps="avcodec avutil"
 +avio_dir_cmd_deps="avformat avutil"
 +avio_reading_deps="avformat avcodec avutil"
 +decoding_encoding_example_deps="avcodec avformat avutil"
 +demuxing_decoding_example_deps="avcodec avformat avutil"
+ encode_audio_example_deps="avcodec avutil"
 +extract_mvs_example_deps="avcodec avformat avutil"
  filter_audio_example_deps="avfilter avutil"
 +filtering_audio_example_deps="avfilter avcodec avformat avutil"
 +filtering_video_example_deps="avfilter avcodec avformat avutil"
 +http_multiclient_example_deps="avformat avutil fork"
  metadata_example_deps="avformat avutil"
 -output_example_deps="avcodec avformat avutil swscale"
 +muxing_example_deps="avcodec avformat avutil swscale"
  qsvdec_example_deps="avcodec avutil libmfx h264_qsv_decoder vaapi_x11"
 -transcode_aac_example_deps="avcodec avformat avresample"
 +remuxing_example_deps="avcodec avformat avutil"
 +resampling_audio_example_deps="avutil swresample"
 +scaling_video_example_deps="avutil swscale"
 +transcode_aac_example_deps="avcodec avformat swresample"
 +transcoding_example_deps="avfilter avcodec avformat avutil"
  
  # libraries, in linking order
  avcodec_deps="avutil"
diff --cc doc/Makefile
index a180fbe,738e601..396d9e0
--- a/doc/Makefile
+++ b/doc/Makefile
@@@ -27,42 -11,25 +27,43 @@@ HTMLPAGES   = $(AVPROGS-yes:%=doc/%.htm
                doc/nut.html                                              \
                doc/platform.html                                         \
  
 -DOCS-$(CONFIG_POD2MAN)                          += $(MANPAGES) $(PODPAGES)
 -DOCS-$(CONFIG_TEXI2HTML)                        += $(HTMLPAGES)
 -DOCS = $(DOCS-yes)
 +TXTPAGES    = doc/fate.txt                                              \
  
 -DOC_EXAMPLES-$(CONFIG_AVCODEC_EXAMPLE)          += avcodec
 -DOC_EXAMPLES-$(CONFIG_ENCODE_AUDIO_EXAMPLE)     += encode_audio
 -DOC_EXAMPLES-$(CONFIG_FILTER_AUDIO_EXAMPLE)     += filter_audio
 -DOC_EXAMPLES-$(CONFIG_METADATA_EXAMPLE)         += metadata
 -DOC_EXAMPLES-$(CONFIG_OUTPUT_EXAMPLE)           += output
 -DOC_EXAMPLES-$(CONFIG_QSVDEC_EXAMPLE)           += qsvdec
 -DOC_EXAMPLES-$(CONFIG_TRANSCODE_AAC_EXAMPLE)    += transcode_aac
 -ALL_DOC_EXAMPLES = avcodec encode_audio filter_audio metadata output transcode_aac
  
 -DOC_EXAMPLES     := $(DOC_EXAMPLES-yes:%=doc/examples/%$(EXESUF))
 -ALL_DOC_EXAMPLES := $(ALL_DOC_EXAMPLES:%=doc/examples/%$(EXESUF))
 -PROGS            += $(DOC_EXAMPLES)
 +DOCS-$(CONFIG_HTMLPAGES) += $(HTMLPAGES)
 +DOCS-$(CONFIG_PODPAGES)  += $(PODPAGES)
 +DOCS-$(CONFIG_MANPAGES)  += $(MANPAGES)
 +DOCS-$(CONFIG_TXTPAGES)  += $(TXTPAGES)
 +DOCS = $(DOCS-yes)
  
 -all: $(DOCS)
 +DOC_EXAMPLES-$(CONFIG_AVIO_DIR_CMD_EXAMPLE)      += avio_dir_cmd
 +DOC_EXAMPLES-$(CONFIG_AVIO_READING_EXAMPLE)      += avio_reading
 +DOC_EXAMPLES-$(CONFIG_DECODING_ENCODING_EXAMPLE) += decoding_encoding
 +DOC_EXAMPLES-$(CONFIG_DEMUXING_DECODING_EXAMPLE) += demuxing_decoding
++DOC_EXAMPLES-$(CONFIG_ENCODE_AUDIO_EXAMPLE)      += encode_audio
 +DOC_EXAMPLES-$(CONFIG_EXTRACT_MVS_EXAMPLE)       += extract_mvs
 +DOC_EXAMPLES-$(CONFIG_FILTER_AUDIO_EXAMPLE)      += filter_audio
 +DOC_EXAMPLES-$(CONFIG_FILTERING_AUDIO_EXAMPLE)   += filtering_audio
 +DOC_EXAMPLES-$(CONFIG_FILTERING_VIDEO_EXAMPLE)   += filtering_video
 +DOC_EXAMPLES-$(CONFIG_HTTP_MULTICLIENT_EXAMPLE)  += http_multiclient
 +DOC_EXAMPLES-$(CONFIG_METADATA_EXAMPLE)          += metadata
 +DOC_EXAMPLES-$(CONFIG_MUXING_EXAMPLE)            += muxing
 +DOC_EXAMPLES-$(CONFIG_QSVDEC_EXAMPLE)            += qsvdec
 +DOC_EXAMPLES-$(CONFIG_REMUXING_EXAMPLE)          += remuxing
 +DOC_EXAMPLES-$(CONFIG_RESAMPLING_AUDIO_EXAMPLE)  += resampling_audio
 +DOC_EXAMPLES-$(CONFIG_SCALING_VIDEO_EXAMPLE)     += scaling_video
 +DOC_EXAMPLES-$(CONFIG_TRANSCODE_AAC_EXAMPLE)     += transcode_aac
 +DOC_EXAMPLES-$(CONFIG_TRANSCODING_EXAMPLE)       += transcoding
 +ALL_DOC_EXAMPLES_LIST = $(DOC_EXAMPLES-) $(DOC_EXAMPLES-yes)
 +
 +DOC_EXAMPLES       := $(DOC_EXAMPLES-yes:%=doc/examples/%$(PROGSSUF)$(EXESUF))
 +ALL_DOC_EXAMPLES   := $(ALL_DOC_EXAMPLES_LIST:%=doc/examples/%$(PROGSSUF)$(EXESUF))
 +ALL_DOC_EXAMPLES_G := $(ALL_DOC_EXAMPLES_LIST:%=doc/examples/%$(PROGSSUF)_g$(EXESUF))
 +PROGS              += $(DOC_EXAMPLES)
 +
 +all-$(CONFIG_DOC): doc
 +
 +doc: documentation
  
  apidoc: doc/doxy/html
  documentation: $(DOCS)
diff --cc doc/examples/.gitignore
index 430d3bf,3f60af7..1a6209b
--- a/doc/examples/.gitignore
+++ b/doc/examples/.gitignore
@@@ -1,18 -1,5 +1,19 @@@
 -/avcodec
 +/avio_dir_cmd
 +/avio_reading
 +/decoding_encoding
 +/demuxing_decoding
++/encode_audio
 +/extract_mvs
  /filter_audio
 +/filtering_audio
 +/filtering_video
 +/http_multiclient
  /metadata
 -/output
 +/muxing
 +/pc-uninstalled
 +/qsvdec
 +/remuxing
 +/resampling_audio
 +/scaling_video
  /transcode_aac
 +/transcoding
diff --cc doc/examples/Makefile
index af38159,0000000..f76e5a2
mode 100644,000000..100644
--- a/doc/examples/Makefile
+++ b/doc/examples/Makefile
@@@ -1,46 -1,0 +1,47 @@@
 +# use pkg-config for getting CFLAGS and LDLIBS
 +FFMPEG_LIBS=    libavdevice                        \
 +                libavformat                        \
 +                libavfilter                        \
 +                libavcodec                         \
 +                libswresample                      \
 +                libswscale                         \
 +                libavutil                          \
 +
 +CFLAGS += -Wall -g
 +CFLAGS := $(shell pkg-config --cflags $(FFMPEG_LIBS)) $(CFLAGS)
 +LDLIBS := $(shell pkg-config --libs $(FFMPEG_LIBS)) $(LDLIBS)
 +
 +EXAMPLES=       avio_dir_cmd                       \
 +                avio_reading                       \
 +                decoding_encoding                  \
 +                demuxing_decoding                  \
++                encode_audio                       \
 +                extract_mvs                        \
 +                filtering_video                    \
 +                filtering_audio                    \
 +                http_multiclient                   \
 +                metadata                           \
 +                muxing                             \
 +                remuxing                           \
 +                resampling_audio                   \
 +                scaling_video                      \
 +                transcode_aac                      \
 +                transcoding                        \
 +
 +OBJS=$(addsuffix .o,$(EXAMPLES))
 +
 +# the following examples make explicit use of the math library
 +avcodec:           LDLIBS += -lm
- decoding_encoding: LDLIBS += -lm
++encode_audio:      LDLIBS += -lm
 +muxing:            LDLIBS += -lm
 +resampling_audio:  LDLIBS += -lm
 +
 +.phony: all clean-test clean
 +
 +all: $(OBJS) $(EXAMPLES)
 +
 +clean-test:
 +	$(RM) test*.pgm test.h264 test.mp2 test.sw test.mpg
 +
 +clean: clean-test
 +	$(RM) $(EXAMPLES) $(OBJS)
diff --cc doc/examples/decoding_encoding.c
index 1c5a78a,0000000..f863bdf
mode 100644,000000..100644
--- a/doc/examples/decoding_encoding.c
+++ b/doc/examples/decoding_encoding.c
@@@ -1,661 -1,0 +1,469 @@@
 +/*
 + * Copyright (c) 2001 Fabrice Bellard
 + *
 + * Permission is hereby granted, free of charge, to any person obtaining a copy
 + * of this software and associated documentation files (the "Software"), to deal
 + * in the Software without restriction, including without limitation the rights
 + * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 + * copies of the Software, and to permit persons to whom the Software is
 + * furnished to do so, subject to the following conditions:
 + *
 + * The above copyright notice and this permission notice shall be included in
 + * all copies or substantial portions of the Software.
 + *
 + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
 + * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 + * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 + * THE SOFTWARE.
 + */
 +
 +/**
 + * @file
 + * libavcodec API use example.
 + *
 + * @example decoding_encoding.c
 + * Note that libavcodec only handles codecs (MPEG, MPEG-4, etc...),
 + * not file formats (AVI, VOB, MP4, MOV, MKV, MXF, FLV, MPEG-TS, MPEG-PS, etc...).
 + * See library 'libavformat' for the format handling
 + */
 +
 +#include <math.h>
 +
 +#include <libavutil/opt.h>
 +#include <libavcodec/avcodec.h>
 +#include <libavutil/channel_layout.h>
 +#include <libavutil/common.h>
 +#include <libavutil/imgutils.h>
 +#include <libavutil/mathematics.h>
 +#include <libavutil/samplefmt.h>
 +
 +#define INBUF_SIZE 4096
 +#define AUDIO_INBUF_SIZE 20480
 +#define AUDIO_REFILL_THRESH 4096
 +
- /* check that a given sample format is supported by the encoder */
- static int check_sample_fmt(AVCodec *codec, enum AVSampleFormat sample_fmt)
- {
-     const enum AVSampleFormat *p = codec->sample_fmts;
- 
-     while (*p != AV_SAMPLE_FMT_NONE) {
-         if (*p == sample_fmt)
-             return 1;
-         p++;
-     }
-     return 0;
- }
- 
- /* just pick the highest supported samplerate */
- static int select_sample_rate(AVCodec *codec)
- {
-     const int *p;
-     int best_samplerate = 0;
- 
-     if (!codec->supported_samplerates)
-         return 44100;
- 
-     p = codec->supported_samplerates;
-     while (*p) {
-         best_samplerate = FFMAX(*p, best_samplerate);
-         p++;
-     }
-     return best_samplerate;
- }
- 
- /* select layout with the highest channel count */
- static int select_channel_layout(AVCodec *codec)
- {
-     const uint64_t *p;
-     uint64_t best_ch_layout = 0;
-     int best_nb_channels   = 0;
- 
-     if (!codec->channel_layouts)
-         return AV_CH_LAYOUT_STEREO;
- 
-     p = codec->channel_layouts;
-     while (*p) {
-         int nb_channels = av_get_channel_layout_nb_channels(*p);
- 
-         if (nb_channels > best_nb_channels) {
-             best_ch_layout    = *p;
-             best_nb_channels = nb_channels;
-         }
-         p++;
-     }
-     return best_ch_layout;
- }
- 
- /*
-  * Audio encoding example
-  */
- static void audio_encode_example(const char *filename)
- {
-     AVCodec *codec;
-     AVCodecContext *c= NULL;
-     AVFrame *frame;
-     AVPacket pkt;
-     int i, j, k, ret, got_output;
-     int buffer_size;
-     FILE *f;
-     uint16_t *samples;
-     float t, tincr;
- 
-     printf("Encode audio file %s\n", filename);
- 
-     /* find the MP2 encoder */
-     codec = avcodec_find_encoder(AV_CODEC_ID_MP2);
-     if (!codec) {
-         fprintf(stderr, "Codec not found\n");
-         exit(1);
-     }
- 
-     c = avcodec_alloc_context3(codec);
-     if (!c) {
-         fprintf(stderr, "Could not allocate audio codec context\n");
-         exit(1);
-     }
- 
-     /* put sample parameters */
-     c->bit_rate = 64000;
- 
-     /* check that the encoder supports s16 pcm input */
-     c->sample_fmt = AV_SAMPLE_FMT_S16;
-     if (!check_sample_fmt(codec, c->sample_fmt)) {
-         fprintf(stderr, "Encoder does not support sample format %s",
-                 av_get_sample_fmt_name(c->sample_fmt));
-         exit(1);
-     }
- 
-     /* select other audio parameters supported by the encoder */
-     c->sample_rate    = select_sample_rate(codec);
-     c->channel_layout = select_channel_layout(codec);
-     c->channels       = av_get_channel_layout_nb_channels(c->channel_layout);
- 
-     /* open it */
-     if (avcodec_open2(c, codec, NULL) < 0) {
-         fprintf(stderr, "Could not open codec\n");
-         exit(1);
-     }
- 
-     f = fopen(filename, "wb");
-     if (!f) {
-         fprintf(stderr, "Could not open %s\n", filename);
-         exit(1);
-     }
- 
-     /* frame containing input raw audio */
-     frame = av_frame_alloc();
-     if (!frame) {
-         fprintf(stderr, "Could not allocate audio frame\n");
-         exit(1);
-     }
- 
-     frame->nb_samples     = c->frame_size;
-     frame->format         = c->sample_fmt;
-     frame->channel_layout = c->channel_layout;
- 
-     /* the codec gives us the frame size, in samples,
-      * we calculate the size of the samples buffer in bytes */
-     buffer_size = av_samples_get_buffer_size(NULL, c->channels, c->frame_size,
-                                              c->sample_fmt, 0);
-     if (buffer_size < 0) {
-         fprintf(stderr, "Could not get sample buffer size\n");
-         exit(1);
-     }
-     samples = av_malloc(buffer_size);
-     if (!samples) {
-         fprintf(stderr, "Could not allocate %d bytes for samples buffer\n",
-                 buffer_size);
-         exit(1);
-     }
-     /* setup the data pointers in the AVFrame */
-     ret = avcodec_fill_audio_frame(frame, c->channels, c->sample_fmt,
-                                    (const uint8_t*)samples, buffer_size, 0);
-     if (ret < 0) {
-         fprintf(stderr, "Could not setup audio frame\n");
-         exit(1);
-     }
- 
-     /* encode a single tone sound */
-     t = 0;
-     tincr = 2 * M_PI * 440.0 / c->sample_rate;
-     for (i = 0; i < 200; i++) {
-         av_init_packet(&pkt);
-         pkt.data = NULL; // packet data will be allocated by the encoder
-         pkt.size = 0;
- 
-         for (j = 0; j < c->frame_size; j++) {
-             samples[2*j] = (int)(sin(t) * 10000);
- 
-             for (k = 1; k < c->channels; k++)
-                 samples[2*j + k] = samples[2*j];
-             t += tincr;
-         }
-         /* encode the samples */
-         ret = avcodec_encode_audio2(c, &pkt, frame, &got_output);
-         if (ret < 0) {
-             fprintf(stderr, "Error encoding audio frame\n");
-             exit(1);
-         }
-         if (got_output) {
-             fwrite(pkt.data, 1, pkt.size, f);
-             av_packet_unref(&pkt);
-         }
-     }
- 
-     /* get the delayed frames */
-     for (got_output = 1; got_output; i++) {
-         ret = avcodec_encode_audio2(c, &pkt, NULL, &got_output);
-         if (ret < 0) {
-             fprintf(stderr, "Error encoding frame\n");
-             exit(1);
-         }
- 
-         if (got_output) {
-             fwrite(pkt.data, 1, pkt.size, f);
-             av_packet_unref(&pkt);
-         }
-     }
-     fclose(f);
- 
-     av_freep(&samples);
-     av_frame_free(&frame);
-     avcodec_free_context(&c);
- }
- 
 +/*
 + * Audio decoding.
 + */
 +static void audio_decode_example(const char *outfilename, const char *filename)
 +{
 +    AVCodec *codec;
 +    AVCodecContext *c= NULL;
 +    int len;
 +    FILE *f, *outfile;
 +    uint8_t inbuf[AUDIO_INBUF_SIZE + AV_INPUT_BUFFER_PADDING_SIZE];
 +    AVPacket avpkt;
 +    AVFrame *decoded_frame = NULL;
 +
 +    av_init_packet(&avpkt);
 +
 +    printf("Decode audio file %s to %s\n", filename, outfilename);
 +
 +    /* find the MPEG audio decoder */
 +    codec = avcodec_find_decoder(AV_CODEC_ID_MP2);
 +    if (!codec) {
 +        fprintf(stderr, "Codec not found\n");
 +        exit(1);
 +    }
 +
 +    c = avcodec_alloc_context3(codec);
 +    if (!c) {
 +        fprintf(stderr, "Could not allocate audio codec context\n");
 +        exit(1);
 +    }
 +
 +    /* open it */
 +    if (avcodec_open2(c, codec, NULL) < 0) {
 +        fprintf(stderr, "Could not open codec\n");
 +        exit(1);
 +    }
 +
 +    f = fopen(filename, "rb");
 +    if (!f) {
 +        fprintf(stderr, "Could not open %s\n", filename);
 +        exit(1);
 +    }
 +    outfile = fopen(outfilename, "wb");
 +    if (!outfile) {
 +        av_free(c);
 +        exit(1);
 +    }
 +
 +    /* decode until eof */
 +    avpkt.data = inbuf;
 +    avpkt.size = fread(inbuf, 1, AUDIO_INBUF_SIZE, f);
 +
 +    while (avpkt.size > 0) {
 +        int i, ch;
 +        int got_frame = 0;
 +
 +        if (!decoded_frame) {
 +            if (!(decoded_frame = av_frame_alloc())) {
 +                fprintf(stderr, "Could not allocate audio frame\n");
 +                exit(1);
 +            }
 +        }
 +
 +        len = avcodec_decode_audio4(c, decoded_frame, &got_frame, &avpkt);
 +        if (len < 0) {
 +            fprintf(stderr, "Error while decoding\n");
 +            exit(1);
 +        }
 +        if (got_frame) {
 +            /* if a frame has been decoded, output it */
 +            int data_size = av_get_bytes_per_sample(c->sample_fmt);
 +            if (data_size < 0) {
 +                /* This should not occur, checking just for paranoia */
 +                fprintf(stderr, "Failed to calculate data size\n");
 +                exit(1);
 +            }
 +            for (i=0; i<decoded_frame->nb_samples; i++)
 +                for (ch=0; ch<c->channels; ch++)
 +                    fwrite(decoded_frame->data[ch] + data_size*i, 1, data_size, outfile);
 +        }
 +        avpkt.size -= len;
 +        avpkt.data += len;
 +        avpkt.dts =
 +        avpkt.pts = AV_NOPTS_VALUE;
 +        if (avpkt.size < AUDIO_REFILL_THRESH) {
 +            /* Refill the input buffer, to avoid trying to decode
 +             * incomplete frames. Instead of this, one could also use
 +             * a parser, or use a proper container format through
 +             * libavformat. */
 +            memmove(inbuf, avpkt.data, avpkt.size);
 +            avpkt.data = inbuf;
 +            len = fread(avpkt.data + avpkt.size, 1,
 +                        AUDIO_INBUF_SIZE - avpkt.size, f);
 +            if (len > 0)
 +                avpkt.size += len;
 +        }
 +    }
 +
 +    fclose(outfile);
 +    fclose(f);
 +
 +    avcodec_free_context(&c);
 +    av_frame_free(&decoded_frame);
 +}
 +
 +/*
 + * Video encoding example
 + */
 +static void video_encode_example(const char *filename, int codec_id)
 +{
 +    AVCodec *codec;
 +    AVCodecContext *c= NULL;
 +    int i, ret, x, y, got_output;
 +    FILE *f;
 +    AVFrame *frame;
 +    AVPacket pkt;
 +    uint8_t endcode[] = { 0, 0, 1, 0xb7 };
 +
 +    printf("Encode video file %s\n", filename);
 +
 +    /* find the video encoder */
 +    codec = avcodec_find_encoder(codec_id);
 +    if (!codec) {
 +        fprintf(stderr, "Codec not found\n");
 +        exit(1);
 +    }
 +
 +    c = avcodec_alloc_context3(codec);
 +    if (!c) {
 +        fprintf(stderr, "Could not allocate video codec context\n");
 +        exit(1);
 +    }
 +
 +    /* put sample parameters */
 +    c->bit_rate = 400000;
 +    /* resolution must be a multiple of two */
 +    c->width = 352;
 +    c->height = 288;
 +    /* frames per second */
 +    c->time_base = (AVRational){1,25};
 +    /* emit one intra frame every ten frames
 +     * check frame pict_type before passing frame
 +     * to encoder, if frame->pict_type is AV_PICTURE_TYPE_I
 +     * then gop_size is ignored and the output of encoder
 +     * will always be I frame irrespective to gop_size
 +     */
 +    c->gop_size = 10;
 +    c->max_b_frames = 1;
 +    c->pix_fmt = AV_PIX_FMT_YUV420P;
 +
 +    if (codec_id == AV_CODEC_ID_H264)
 +        av_opt_set(c->priv_data, "preset", "slow", 0);
 +
 +    /* open it */
 +    if (avcodec_open2(c, codec, NULL) < 0) {
 +        fprintf(stderr, "Could not open codec\n");
 +        exit(1);
 +    }
 +
 +    f = fopen(filename, "wb");
 +    if (!f) {
 +        fprintf(stderr, "Could not open %s\n", filename);
 +        exit(1);
 +    }
 +
 +    frame = av_frame_alloc();
 +    if (!frame) {
 +        fprintf(stderr, "Could not allocate video frame\n");
 +        exit(1);
 +    }
 +    frame->format = c->pix_fmt;
 +    frame->width  = c->width;
 +    frame->height = c->height;
 +
 +    /* the image can be allocated by any means and av_image_alloc() is
 +     * just the most convenient way if av_malloc() is to be used */
 +    ret = av_image_alloc(frame->data, frame->linesize, c->width, c->height,
 +                         c->pix_fmt, 32);
 +    if (ret < 0) {
 +        fprintf(stderr, "Could not allocate raw picture buffer\n");
 +        exit(1);
 +    }
 +
 +    /* encode 1 second of video */
 +    for (i = 0; i < 25; i++) {
 +        av_init_packet(&pkt);
 +        pkt.data = NULL;    // packet data will be allocated by the encoder
 +        pkt.size = 0;
 +
 +        fflush(stdout);
 +        /* prepare a dummy image */
 +        /* Y */
 +        for (y = 0; y < c->height; y++) {
 +            for (x = 0; x < c->width; x++) {
 +                frame->data[0][y * frame->linesize[0] + x] = x + y + i * 3;
 +            }
 +        }
 +
 +        /* Cb and Cr */
 +        for (y = 0; y < c->height/2; y++) {
 +            for (x = 0; x < c->width/2; x++) {
 +                frame->data[1][y * frame->linesize[1] + x] = 128 + y + i * 2;
 +                frame->data[2][y * frame->linesize[2] + x] = 64 + x + i * 5;
 +            }
 +        }
 +
 +        frame->pts = i;
 +
 +        /* encode the image */
 +        ret = avcodec_encode_video2(c, &pkt, frame, &got_output);
 +        if (ret < 0) {
 +            fprintf(stderr, "Error encoding frame\n");
 +            exit(1);
 +        }
 +
 +        if (got_output) {
 +            printf("Write frame %3d (size=%5d)\n", i, pkt.size);
 +            fwrite(pkt.data, 1, pkt.size, f);
 +            av_packet_unref(&pkt);
 +        }
 +    }
 +
 +    /* get the delayed frames */
 +    for (got_output = 1; got_output; i++) {
 +        fflush(stdout);
 +
 +        ret = avcodec_encode_video2(c, &pkt, NULL, &got_output);
 +        if (ret < 0) {
 +            fprintf(stderr, "Error encoding frame\n");
 +            exit(1);
 +        }
 +
 +        if (got_output) {
 +            printf("Write frame %3d (size=%5d)\n", i, pkt.size);
 +            fwrite(pkt.data, 1, pkt.size, f);
 +            av_packet_unref(&pkt);
 +        }
 +    }
 +
 +    /* add sequence end code to have a real MPEG file */
 +    fwrite(endcode, 1, sizeof(endcode), f);
 +    fclose(f);
 +
 +    avcodec_free_context(&c);
 +    av_freep(&frame->data[0]);
 +    av_frame_free(&frame);
 +    printf("\n");
 +}
 +
 +/*
 + * Video decoding example
 + */
 +
 +static void pgm_save(unsigned char *buf, int wrap, int xsize, int ysize,
 +                     char *filename)
 +{
 +    FILE *f;
 +    int i;
 +
 +    f = fopen(filename,"w");
 +    fprintf(f, "P5\n%d %d\n%d\n", xsize, ysize, 255);
 +    for (i = 0; i < ysize; i++)
 +        fwrite(buf + i * wrap, 1, xsize, f);
 +    fclose(f);
 +}
 +
 +static int decode_write_frame(const char *outfilename, AVCodecContext *avctx,
 +                              AVFrame *frame, int *frame_count, AVPacket *pkt, int last)
 +{
 +    int len, got_frame;
 +    char buf[1024];
 +
 +    len = avcodec_decode_video2(avctx, frame, &got_frame, pkt);
 +    if (len < 0) {
 +        fprintf(stderr, "Error while decoding frame %d\n", *frame_count);
 +        return len;
 +    }
 +    if (got_frame) {
 +        printf("Saving %sframe %3d\n", last ? "last " : "", *frame_count);
 +        fflush(stdout);
 +
 +        /* the picture is allocated by the decoder, no need to free it */
 +        snprintf(buf, sizeof(buf), outfilename, *frame_count);
 +        pgm_save(frame->data[0], frame->linesize[0],
 +                 frame->width, frame->height, buf);
 +        (*frame_count)++;
 +    }
 +    if (pkt->data) {
 +        pkt->size -= len;
 +        pkt->data += len;
 +    }
 +    return 0;
 +}
 +
 +static void video_decode_example(const char *outfilename, const char *filename)
 +{
 +    AVCodec *codec;
 +    AVCodecContext *c= NULL;
 +    int frame_count;
 +    FILE *f;
 +    AVFrame *frame;
 +    uint8_t inbuf[INBUF_SIZE + AV_INPUT_BUFFER_PADDING_SIZE];
 +    AVPacket avpkt;
 +
 +    av_init_packet(&avpkt);
 +
 +    /* set end of buffer to 0 (this ensures that no overreading happens for damaged MPEG streams) */
 +    memset(inbuf + INBUF_SIZE, 0, AV_INPUT_BUFFER_PADDING_SIZE);
 +
 +    printf("Decode video file %s to %s\n", filename, outfilename);
 +
 +    /* find the MPEG-1 video decoder */
 +    codec = avcodec_find_decoder(AV_CODEC_ID_MPEG1VIDEO);
 +    if (!codec) {
 +        fprintf(stderr, "Codec not found\n");
 +        exit(1);
 +    }
 +
 +    c = avcodec_alloc_context3(codec);
 +    if (!c) {
 +        fprintf(stderr, "Could not allocate video codec context\n");
 +        exit(1);
 +    }
 +
 +    if (codec->capabilities & AV_CODEC_CAP_TRUNCATED)
 +        c->flags |= AV_CODEC_FLAG_TRUNCATED; // we do not send complete frames
 +
 +    /* For some codecs, such as msmpeg4 and mpeg4, width and height
 +       MUST be initialized there because this information is not
 +       available in the bitstream. */
 +
 +    /* open it */
 +    if (avcodec_open2(c, codec, NULL) < 0) {
 +        fprintf(stderr, "Could not open codec\n");
 +        exit(1);
 +    }
 +
 +    f = fopen(filename, "rb");
 +    if (!f) {
 +        fprintf(stderr, "Could not open %s\n", filename);
 +        exit(1);
 +    }
 +
 +    frame = av_frame_alloc();
 +    if (!frame) {
 +        fprintf(stderr, "Could not allocate video frame\n");
 +        exit(1);
 +    }
 +
 +    frame_count = 0;
 +    for (;;) {
 +        avpkt.size = fread(inbuf, 1, INBUF_SIZE, f);
 +        if (avpkt.size == 0)
 +            break;
 +
 +        /* NOTE1: some codecs are stream based (mpegvideo, mpegaudio)
 +           and this is the only method to use them because you cannot
 +           know the compressed data size before analysing it.
 +
 +           BUT some other codecs (msmpeg4, mpeg4) are inherently frame
 +           based, so you must call them with all the data for one
 +           frame exactly. You must also initialize 'width' and
 +           'height' before initializing them. */
 +
 +        /* NOTE2: some codecs allow the raw parameters (frame size,
 +           sample rate) to be changed at any frame. We handle this, so
 +           you should also take care of it */
 +
 +        /* here, we use a stream based decoder (mpeg1video), so we
 +           feed decoder and see if it could decode a frame */
 +        avpkt.data = inbuf;
 +        while (avpkt.size > 0)
 +            if (decode_write_frame(outfilename, c, frame, &frame_count, &avpkt, 0) < 0)
 +                exit(1);
 +    }
 +
 +    /* Some codecs, such as MPEG, transmit the I- and P-frame with a
 +       latency of one frame. You must do the following to have a
 +       chance to get the last frame of the video. */
 +    avpkt.data = NULL;
 +    avpkt.size = 0;
 +    decode_write_frame(outfilename, c, frame, &frame_count, &avpkt, 1);
 +
 +    fclose(f);
 +
 +    avcodec_free_context(&c);
 +    av_frame_free(&frame);
 +    printf("\n");
 +}
 +
 +int main(int argc, char **argv)
 +{
 +    const char *output_type;
 +
 +    /* register all the codecs */
 +    avcodec_register_all();
 +
 +    if (argc < 2) {
 +        printf("usage: %s output_type\n"
 +               "API example program to decode/encode a media stream with libavcodec.\n"
 +               "This program generates a synthetic stream and encodes it to a file\n"
 +               "named test.h264, test.mp2 or test.mpg depending on output_type.\n"
 +               "The encoded stream is then decoded and written to a raw data output.\n"
 +               "output_type must be chosen between 'h264', 'mp2', 'mpg'.\n",
 +               argv[0]);
 +        return 1;
 +    }
 +    output_type = argv[1];
 +
 +    if (!strcmp(output_type, "h264")) {
 +        video_encode_example("test.h264", AV_CODEC_ID_H264);
 +    } else if (!strcmp(output_type, "mp2")) {
-         audio_encode_example("test.mp2");
 +        audio_decode_example("test.pcm", "test.mp2");
 +    } else if (!strcmp(output_type, "mpg")) {
 +        video_encode_example("test.mpg", AV_CODEC_ID_MPEG1VIDEO);
 +        video_decode_example("test%02d.pgm", "test.mpg");
 +    } else {
 +        fprintf(stderr, "Invalid output type '%s', choose between 'h264', 'mp2', or 'mpg'\n",
 +                output_type);
 +        return 1;
 +    }
 +
 +    return 0;
 +}
diff --cc doc/examples/encode_audio.c
index 0000000,cabe589..5932521
mode 000000,100644..100644
--- a/doc/examples/encode_audio.c
+++ b/doc/examples/encode_audio.c
@@@ -1,0 -1,211 +1,235 @@@
+ /*
 - * copyright (c) 2001 Fabrice Bellard
++ * Copyright (c) 2001 Fabrice Bellard
+  *
 - * This file is part of Libav.
++ * Permission is hereby granted, free of charge, to any person obtaining a copy
++ * of this software and associated documentation files (the "Software"), to deal
++ * in the Software without restriction, including without limitation the rights
++ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
++ * copies of the Software, and to permit persons to whom the Software is
++ * furnished to do so, subject to the following conditions:
+  *
 - * Libav is free software; you can redistribute it and/or
 - * modify it under the terms of the GNU Lesser General Public
 - * License as published by the Free Software Foundation; either
 - * version 2.1 of the License, or (at your option) any later version.
++ * The above copyright notice and this permission notice shall be included in
++ * all copies or substantial portions of the Software.
+  *
 - * Libav is distributed in the hope that it will be useful,
 - * but WITHOUT ANY WARRANTY; without even the implied warranty of
 - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 - * Lesser General Public License for more details.
 - *
 - * You should have received a copy of the GNU Lesser General Public
 - * License along with Libav; if not, write to the Free Software
 - * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
++ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
++ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
++ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
++ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
++ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
++ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
++ * THE SOFTWARE.
+  */
+ 
+ /**
+  * @file
+  * audio encoding with libavcodec API example.
+  *
+  * @example encode_audio.c
+  */
+ 
+ #include <stdint.h>
+ #include <stdio.h>
+ #include <stdlib.h>
+ 
+ #include "libavcodec/avcodec.h"
+ 
+ #include "libavutil/channel_layout.h"
+ #include "libavutil/common.h"
+ #include "libavutil/frame.h"
+ #include "libavutil/samplefmt.h"
+ 
+ /* check that a given sample format is supported by the encoder */
+ static int check_sample_fmt(AVCodec *codec, enum AVSampleFormat sample_fmt)
+ {
+     const enum AVSampleFormat *p = codec->sample_fmts;
+ 
+     while (*p != AV_SAMPLE_FMT_NONE) {
+         if (*p == sample_fmt)
+             return 1;
+         p++;
+     }
+     return 0;
+ }
+ 
+ /* just pick the highest supported samplerate */
+ static int select_sample_rate(AVCodec *codec)
+ {
+     const int *p;
+     int best_samplerate = 0;
+ 
+     if (!codec->supported_samplerates)
+         return 44100;
+ 
+     p = codec->supported_samplerates;
+     while (*p) {
+         best_samplerate = FFMAX(*p, best_samplerate);
+         p++;
+     }
+     return best_samplerate;
+ }
+ 
+ /* select layout with the highest channel count */
+ static int select_channel_layout(AVCodec *codec)
+ {
+     const uint64_t *p;
+     uint64_t best_ch_layout = 0;
+     int best_nb_channels   = 0;
+ 
+     if (!codec->channel_layouts)
+         return AV_CH_LAYOUT_STEREO;
+ 
+     p = codec->channel_layouts;
+     while (*p) {
+         int nb_channels = av_get_channel_layout_nb_channels(*p);
+ 
+         if (nb_channels > best_nb_channels) {
+             best_ch_layout    = *p;
+             best_nb_channels = nb_channels;
+         }
+         p++;
+     }
+     return best_ch_layout;
+ }
+ 
+ int main(int argc, char **argv)
+ {
+     const char *filename;
+     AVCodec *codec;
+     AVCodecContext *c= NULL;
+     AVFrame *frame;
+     AVPacket pkt;
+     int i, j, k, ret, got_output;
+     int buffer_size;
+     FILE *f;
+     uint16_t *samples;
+     float t, tincr;
+ 
+     if (argc <= 1) {
+         fprintf(stderr, "Usage: %s <output file>\n", argv[0]);
+         return 0;
+     }
+     filename = argv[1];
+ 
+     /* register all the codecs */
+     avcodec_register_all();
+ 
+     /* find the MP2 encoder */
+     codec = avcodec_find_encoder(AV_CODEC_ID_MP2);
+     if (!codec) {
 -        fprintf(stderr, "codec not found\n");
++        fprintf(stderr, "Codec not found\n");
+         exit(1);
+     }
+ 
+     c = avcodec_alloc_context3(codec);
++    if (!c) {
++        fprintf(stderr, "Could not allocate audio codec context\n");
++        exit(1);
++    }
+ 
+     /* put sample parameters */
+     c->bit_rate = 64000;
+ 
+     /* check that the encoder supports s16 pcm input */
+     c->sample_fmt = AV_SAMPLE_FMT_S16;
+     if (!check_sample_fmt(codec, c->sample_fmt)) {
 -        fprintf(stderr, "encoder does not support %s",
++        fprintf(stderr, "Encoder does not support sample format %s",
+                 av_get_sample_fmt_name(c->sample_fmt));
+         exit(1);
+     }
+ 
+     /* select other audio parameters supported by the encoder */
+     c->sample_rate    = select_sample_rate(codec);
+     c->channel_layout = select_channel_layout(codec);
+     c->channels       = av_get_channel_layout_nb_channels(c->channel_layout);
+ 
+     /* open it */
+     if (avcodec_open2(c, codec, NULL) < 0) {
 -        fprintf(stderr, "could not open codec\n");
++        fprintf(stderr, "Could not open codec\n");
+         exit(1);
+     }
+ 
+     f = fopen(filename, "wb");
+     if (!f) {
 -        fprintf(stderr, "could not open %s\n", filename);
++        fprintf(stderr, "Could not open %s\n", filename);
+         exit(1);
+     }
+ 
+     /* frame containing input raw audio */
+     frame = av_frame_alloc();
+     if (!frame) {
 -        fprintf(stderr, "could not allocate audio frame\n");
++        fprintf(stderr, "Could not allocate audio frame\n");
+         exit(1);
+     }
+ 
+     frame->nb_samples     = c->frame_size;
+     frame->format         = c->sample_fmt;
+     frame->channel_layout = c->channel_layout;
+ 
+     /* the codec gives us the frame size, in samples,
+      * we calculate the size of the samples buffer in bytes */
+     buffer_size = av_samples_get_buffer_size(NULL, c->channels, c->frame_size,
+                                              c->sample_fmt, 0);
++    if (buffer_size < 0) {
++        fprintf(stderr, "Could not get sample buffer size\n");
++        exit(1);
++    }
+     samples = av_malloc(buffer_size);
+     if (!samples) {
 -        fprintf(stderr, "could not allocate %d bytes for samples buffer\n",
++        fprintf(stderr, "Could not allocate %d bytes for samples buffer\n",
+                 buffer_size);
+         exit(1);
+     }
+     /* setup the data pointers in the AVFrame */
+     ret = avcodec_fill_audio_frame(frame, c->channels, c->sample_fmt,
+                                    (const uint8_t*)samples, buffer_size, 0);
+     if (ret < 0) {
 -        fprintf(stderr, "could not setup audio frame\n");
++        fprintf(stderr, "Could not setup audio frame\n");
+         exit(1);
+     }
+ 
+     /* encode a single tone sound */
+     t = 0;
+     tincr = 2 * M_PI * 440.0 / c->sample_rate;
 -    for(i=0;i<200;i++) {
++    for (i = 0; i < 200; i++) {
+         av_init_packet(&pkt);
+         pkt.data = NULL; // packet data will be allocated by the encoder
+         pkt.size = 0;
+ 
+         for (j = 0; j < c->frame_size; j++) {
+             samples[2*j] = (int)(sin(t) * 10000);
+ 
+             for (k = 1; k < c->channels; k++)
+                 samples[2*j + k] = samples[2*j];
+             t += tincr;
+         }
+         /* encode the samples */
+         ret = avcodec_encode_audio2(c, &pkt, frame, &got_output);
+         if (ret < 0) {
 -            fprintf(stderr, "error encoding audio frame\n");
++            fprintf(stderr, "Error encoding audio frame\n");
+             exit(1);
+         }
+         if (got_output) {
+             fwrite(pkt.data, 1, pkt.size, f);
+             av_packet_unref(&pkt);
+         }
+     }
++
++    /* get the delayed frames */
++    for (got_output = 1; got_output; i++) {
++        ret = avcodec_encode_audio2(c, &pkt, NULL, &got_output);
++        if (ret < 0) {
++            fprintf(stderr, "Error encoding frame\n");
++            exit(1);
++        }
++
++        if (got_output) {
++            fwrite(pkt.data, 1, pkt.size, f);
++            av_packet_unref(&pkt);
++        }
++    }
+     fclose(f);
+ 
+     av_freep(&samples);
+     av_frame_free(&frame);
+     avcodec_free_context(&c);
+ }



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