[FFmpeg-cvslog] lavc: add codec parameters API
Anton Khirnov
git at videolan.org
Thu Mar 31 22:22:41 CEST 2016
ffmpeg | branch: master | Anton Khirnov <anton at khirnov.net> | Wed Jun 18 20:42:13 2014 +0200| [998e1b8f521b73e1ed3a13caaabcf79eb401cf0d] | committer: Anton Khirnov
lavc: add codec parameters API
This API is intended to allow passing around codec parameters without
using full AVCodecContext (which also contains codec options and
encoder/decoder state).
> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=998e1b8f521b73e1ed3a13caaabcf79eb401cf0d
---
doc/APIchanges | 3 +
libavcodec/avcodec.h | 163 ++++++++++++++++++++++++++++++++++++++++++++++++++
libavcodec/utils.c | 152 ++++++++++++++++++++++++++++++++++++++++++++++
libavcodec/version.h | 2 +-
4 files changed, 319 insertions(+), 1 deletion(-)
diff --git a/doc/APIchanges b/doc/APIchanges
index b84fa4e..9e11ccc 100644
--- a/doc/APIchanges
+++ b/doc/APIchanges
@@ -13,6 +13,9 @@ libavutil: 2015-08-28
API changes, most recent first:
+2016-xx-xx - lavc 57.14.0 - avcodec.h
+ xxxxxxx - Add AVCodecParameters and its related API.
+
2016-xx-xx - xxxxxxx - lavf 57.4.0 - avformat.h
Add AVFormatContext.protocol_whitelist and protocol_blacklist.
Add 'protocol_whitelist' and 'protocol_blacklist' private options for
diff --git a/libavcodec/avcodec.h b/libavcodec/avcodec.h
index 3deefb0..4d6b2d0 100644
--- a/libavcodec/avcodec.h
+++ b/libavcodec/avcodec.h
@@ -3336,6 +3336,127 @@ typedef struct AVSubtitle {
} AVSubtitle;
/**
+ * This struct describes the properties of an encoded stream.
+ *
+ * sizeof(AVCodecParameters) is not a part of the public ABI, this struct must
+ * be allocated with avcodec_parameters_alloc() and freed with
+ * avcodec_parameters_free().
+ */
+typedef struct AVCodecParameters {
+ /**
+ * General type of the encoded data.
+ */
+ enum AVMediaType codec_type;
+ /**
+ * Specific type of the encoded data (the codec used).
+ */
+ enum AVCodecID codec_id;
+ /**
+ * Additional information about the codec (corresponds to the AVI FOURCC).
+ */
+ uint32_t codec_tag;
+
+ /**
+ * Extra binary data needed for initializing the decoder, codec-dependent.
+ *
+ * Must be allocated with av_malloc() and will be freed by
+ * avcodec_parameters_free(). The allocated size of extradata must be at
+ * least extradata_size + AV_INPUT_BUFFER_PADDING_SIZE, with the padding
+ * bytes zeroed.
+ */
+ uint8_t *extradata;
+ /**
+ * Size of the extradata content in bytes.
+ */
+ int extradata_size;
+
+ /**
+ * - video: the pixel format, the value corresponds to enum AVPixelFormat.
+ * - audio: the sample format, the value corresponds to enum AVSampleFormat.
+ */
+ int format;
+
+ /**
+ * The average bitrate of the encoded data (in bits per second).
+ */
+ int bit_rate;
+
+ int bits_per_coded_sample;
+
+ /**
+ * Codec-specific bitstream restrictions that the stream conforms to.
+ */
+ int profile;
+ int level;
+
+ /**
+ * Video only. The dimensions of the video frame in pixels.
+ */
+ int width;
+ int height;
+
+ /**
+ * Video only. The aspect ratio (width / height) which a single pixel
+ * should have when displayed.
+ *
+ * When the aspect ratio is unknown / undefined, the numerator should be
+ * set to 0 (the denominator may have any value).
+ */
+ AVRational sample_aspect_ratio;
+
+ /**
+ * Video only. The order of the fields in interlaced video.
+ */
+ enum AVFieldOrder field_order;
+
+ /**
+ * Video only. Additional colorspace characteristics.
+ */
+ enum AVColorRange color_range;
+ enum AVColorPrimaries color_primaries;
+ enum AVColorTransferCharacteristic color_trc;
+ enum AVColorSpace color_space;
+ enum AVChromaLocation chroma_location;
+
+ /**
+ * Audio only. The channel layout bitmask. May be 0 if the channel layout is
+ * unknown or unspecified, otherwise the number of bits set must be equal to
+ * the channels field.
+ */
+ uint64_t channel_layout;
+ /**
+ * Audio only. The number of audio channels.
+ */
+ int channels;
+ /**
+ * Audio only. The number of audio samples per second.
+ */
+ int sample_rate;
+ /**
+ * Audio only. The number of bytes per coded audio frame, required by some
+ * formats.
+ *
+ * Corresponds to nBlockAlign in WAVEFORMATEX.
+ */
+ int block_align;
+
+ /**
+ * Audio only. The amount of padding (in samples) inserted by the encoder at
+ * the beginning of the audio. I.e. this number of leading decoded samples
+ * must be discarded by the caller to get the original audio without leading
+ * padding.
+ */
+ int initial_padding;
+ /**
+ * Audio only. The amount of padding (in samples) appended by the encoder to
+ * the end of the audio. I.e. this number of decoded samples must be
+ * discarded by the caller from the end of the stream to get the original
+ * audio without any trailing padding.
+ */
+ int trailing_padding;
+} AVCodecParameters;
+
+/**
* If c is NULL, returns the first registered codec,
* if c is non-NULL, returns the next registered codec after c,
* or NULL if c is the last one.
@@ -3434,6 +3555,48 @@ const AVClass *avcodec_get_class(void);
int avcodec_copy_context(AVCodecContext *dest, const AVCodecContext *src);
/**
+ * Allocate a new AVCodecParameters and set its fields to default values
+ * (unknown/invalid/0). The returned struct must be freed with
+ * avcodec_parameters_free().
+ */
+AVCodecParameters *avcodec_parameters_alloc(void);
+
+/**
+ * Free an AVCodecParameters instance and everything associated with it and
+ * write NULL to the supplied pointer.
+ */
+void avcodec_parameters_free(AVCodecParameters **par);
+
+/**
+ * Copy the contents of src to dst. Any allocated fields in dst are freed and
+ * replaced with newly allocated duplicates of the corresponding fields in src.
+ *
+ * @return >= 0 on success, a negative AVERROR code on failure.
+ */
+int avcodec_parameters_copy(AVCodecParameters *dst, const AVCodecParameters *src);
+
+/**
+ * Fill the parameters struct based on the values from the supplied codec
+ * context. Any allocated fields in par are freed and replaced with duplicates
+ * of the corresponding fields in codec.
+ *
+ * @return >= 0 on success, a negative AVERROR code on failure
+ */
+int avcodec_parameters_from_context(AVCodecParameters *par,
+ const AVCodecContext *codec);
+
+/**
+ * Fill the codec context based on the values from the supplied codec
+ * parameters. Any allocated fields in codec that have a corresponding field in
+ * par are freed and replaced with duplicates of the corresponding field in par.
+ * Fields in codec that do not have a counterpart in par are not touched.
+ *
+ * @return >= 0 on success, a negative AVERROR code on failure.
+ */
+int avcodec_parameters_to_context(AVCodecContext *codec,
+ const AVCodecParameters *par);
+
+/**
* Initialize the AVCodecContext to use the given AVCodec. Prior to using this
* function the context has to be allocated with avcodec_alloc_context3().
*
diff --git a/libavcodec/utils.c b/libavcodec/utils.c
index 94ec1e8..86a67e1 100644
--- a/libavcodec/utils.c
+++ b/libavcodec/utils.c
@@ -2440,3 +2440,155 @@ AVCPBProperties *ff_add_cpb_side_data(AVCodecContext *avctx)
return props;
}
+
+static void codec_parameters_reset(AVCodecParameters *par)
+{
+ av_freep(&par->extradata);
+
+ memset(par, 0, sizeof(*par));
+
+ par->codec_type = AVMEDIA_TYPE_UNKNOWN;
+ par->codec_id = AV_CODEC_ID_NONE;
+ par->format = -1;
+ par->field_order = AV_FIELD_UNKNOWN;
+ par->color_range = AVCOL_RANGE_UNSPECIFIED;
+ par->color_primaries = AVCOL_PRI_UNSPECIFIED;
+ par->color_trc = AVCOL_TRC_UNSPECIFIED;
+ par->color_space = AVCOL_SPC_UNSPECIFIED;
+ par->chroma_location = AVCHROMA_LOC_UNSPECIFIED;
+ par->sample_aspect_ratio = (AVRational){ 0, 1 };
+}
+
+AVCodecParameters *avcodec_parameters_alloc(void)
+{
+ AVCodecParameters *par = av_mallocz(sizeof(*par));
+
+ if (!par)
+ return NULL;
+ codec_parameters_reset(par);
+ return par;
+}
+
+void avcodec_parameters_free(AVCodecParameters **ppar)
+{
+ AVCodecParameters *par = *ppar;
+
+ if (!par)
+ return;
+ codec_parameters_reset(par);
+
+ av_freep(ppar);
+}
+
+int avcodec_parameters_copy(AVCodecParameters *dst, const AVCodecParameters *src)
+{
+ codec_parameters_reset(dst);
+ memcpy(dst, src, sizeof(*dst));
+
+ dst->extradata = NULL;
+ dst->extradata_size = 0;
+ if (src->extradata) {
+ dst->extradata = av_mallocz(src->extradata_size + AV_INPUT_BUFFER_PADDING_SIZE);
+ if (!dst->extradata)
+ return AVERROR(ENOMEM);
+ memcpy(dst->extradata, src->extradata, src->extradata_size);
+ dst->extradata_size = src->extradata_size;
+ }
+
+ return 0;
+}
+
+int avcodec_parameters_from_context(AVCodecParameters *par,
+ const AVCodecContext *codec)
+{
+ codec_parameters_reset(par);
+
+ par->codec_type = codec->codec_type;
+ par->codec_id = codec->codec_id;
+ par->codec_tag = codec->codec_tag;
+
+ par->bit_rate = codec->bit_rate;
+ par->bits_per_coded_sample = codec->bits_per_coded_sample;
+ par->profile = codec->profile;
+ par->level = codec->level;
+
+ switch (par->codec_type) {
+ case AVMEDIA_TYPE_VIDEO:
+ par->format = codec->pix_fmt;
+ par->width = codec->width;
+ par->height = codec->height;
+ par->field_order = codec->field_order;
+ par->color_range = codec->color_range;
+ par->color_primaries = codec->color_primaries;
+ par->color_trc = codec->color_trc;
+ par->color_space = codec->colorspace;
+ par->chroma_location = codec->chroma_sample_location;
+ par->sample_aspect_ratio = codec->sample_aspect_ratio;
+ break;
+ case AVMEDIA_TYPE_AUDIO:
+ par->format = codec->sample_fmt;
+ par->channel_layout = codec->channel_layout;
+ par->channels = codec->channels;
+ par->sample_rate = codec->sample_rate;
+ par->block_align = codec->block_align;
+ par->initial_padding = codec->initial_padding;
+ break;
+ }
+
+ if (codec->extradata) {
+ par->extradata = av_mallocz(codec->extradata_size + AV_INPUT_BUFFER_PADDING_SIZE);
+ if (!par->extradata)
+ return AVERROR(ENOMEM);
+ memcpy(par->extradata, codec->extradata, codec->extradata_size);
+ par->extradata_size = codec->extradata_size;
+ }
+
+ return 0;
+}
+
+int avcodec_parameters_to_context(AVCodecContext *codec,
+ const AVCodecParameters *par)
+{
+ codec->codec_type = par->codec_type;
+ codec->codec_id = par->codec_id;
+ codec->codec_tag = par->codec_tag;
+
+ codec->bit_rate = par->bit_rate;
+ codec->bits_per_coded_sample = par->bits_per_coded_sample;
+ codec->profile = par->profile;
+ codec->level = par->level;
+
+ switch (par->codec_type) {
+ case AVMEDIA_TYPE_VIDEO:
+ codec->pix_fmt = par->format;
+ codec->width = par->width;
+ codec->height = par->height;
+ codec->field_order = par->field_order;
+ codec->color_range = par->color_range;
+ codec->color_primaries = par->color_primaries;
+ codec->color_trc = par->color_trc;
+ codec->colorspace = par->color_space;
+ codec->chroma_sample_location = par->chroma_location;
+ codec->sample_aspect_ratio = par->sample_aspect_ratio;
+ break;
+ case AVMEDIA_TYPE_AUDIO:
+ codec->sample_fmt = par->format;
+ codec->channel_layout = par->channel_layout;
+ codec->channels = par->channels;
+ codec->sample_rate = par->sample_rate;
+ codec->block_align = par->block_align;
+ codec->initial_padding = par->initial_padding;
+ break;
+ }
+
+ if (par->extradata) {
+ av_freep(&codec->extradata);
+ codec->extradata = av_mallocz(par->extradata_size + AV_INPUT_BUFFER_PADDING_SIZE);
+ if (!codec->extradata)
+ return AVERROR(ENOMEM);
+ memcpy(codec->extradata, par->extradata, par->extradata_size);
+ codec->extradata_size = par->extradata_size;
+ }
+
+ return 0;
+}
diff --git a/libavcodec/version.h b/libavcodec/version.h
index 2cdad5a..d247c09 100644
--- a/libavcodec/version.h
+++ b/libavcodec/version.h
@@ -28,7 +28,7 @@
#include "libavutil/version.h"
#define LIBAVCODEC_VERSION_MAJOR 57
-#define LIBAVCODEC_VERSION_MINOR 13
+#define LIBAVCODEC_VERSION_MINOR 14
#define LIBAVCODEC_VERSION_MICRO 0
#define LIBAVCODEC_VERSION_INT AV_VERSION_INT(LIBAVCODEC_VERSION_MAJOR, \
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