[FFmpeg-devel] [PATCH 1/1] Add Sega FILM muxer
misty at brew.sh
misty at brew.sh
Mon Mar 26 18:14:59 EEST 2018
From: Misty De Meo <mistydemeo at gmail.com>
---
Changelog | 1 +
doc/general.texi | 2 +-
libavformat/Makefile | 1 +
libavformat/allformats.c | 1 +
libavformat/segafilmenc.c | 377 ++++++++++++++++++++++++++++++++++++++++++++++
libavformat/version.h | 2 +-
6 files changed, 382 insertions(+), 2 deletions(-)
create mode 100644 libavformat/segafilmenc.c
diff --git a/Changelog b/Changelog
index 30a8978db4..0ff62ff69d 100644
--- a/Changelog
+++ b/Changelog
@@ -48,6 +48,7 @@ version <next>:
- drmeter audio filter
- hapqa_extract bitstream filter
- filter_units bitstream filter
+- segafilm muxer
version 3.4:
diff --git a/doc/general.texi b/doc/general.texi
index c5d46d3404..b5b7695bd4 100644
--- a/doc/general.texi
+++ b/doc/general.texi
@@ -551,7 +551,7 @@ library:
@item SAP @tab X @tab X
@item SBG @tab @tab X
@item SDP @tab @tab X
- at item Sega FILM/CPK @tab @tab X
+ at item Sega FILM/CPK @tab X @tab X
@tab Used in many Sega Saturn console games.
@item Silicon Graphics Movie @tab @tab X
@item Sierra SOL @tab @tab X
diff --git a/libavformat/Makefile b/libavformat/Makefile
index 39ec68c28b..4abb992b14 100644
--- a/libavformat/Makefile
+++ b/libavformat/Makefile
@@ -462,6 +462,7 @@ OBJS-$(CONFIG_SDR2_DEMUXER) += sdr2.o
OBJS-$(CONFIG_SDS_DEMUXER) += sdsdec.o
OBJS-$(CONFIG_SDX_DEMUXER) += sdxdec.o
OBJS-$(CONFIG_SEGAFILM_DEMUXER) += segafilm.o
+OBJS-$(CONFIG_SEGAFILM_MUXER) += segafilmenc.o
OBJS-$(CONFIG_SEGMENT_MUXER) += segment.o
OBJS-$(CONFIG_SHORTEN_DEMUXER) += shortendec.o rawdec.o
OBJS-$(CONFIG_SIFF_DEMUXER) += siff.o
diff --git a/libavformat/allformats.c b/libavformat/allformats.c
index 9dc5ce8a76..dfd964f07a 100644
--- a/libavformat/allformats.c
+++ b/libavformat/allformats.c
@@ -364,6 +364,7 @@ extern AVInputFormat ff_sdr2_demuxer;
extern AVInputFormat ff_sds_demuxer;
extern AVInputFormat ff_sdx_demuxer;
extern AVInputFormat ff_segafilm_demuxer;
+extern AVOutputFormat ff_segafilm_muxer;
extern AVOutputFormat ff_segment_muxer;
extern AVOutputFormat ff_stream_segment_muxer;
extern AVInputFormat ff_shorten_demuxer;
diff --git a/libavformat/segafilmenc.c b/libavformat/segafilmenc.c
new file mode 100644
index 0000000000..453eb7d6ba
--- /dev/null
+++ b/libavformat/segafilmenc.c
@@ -0,0 +1,377 @@
+/*
+ * Sega FILM Format (CPK) Muxer
+ * Copyright (C) 2003 The FFmpeg project
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg 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.
+ *
+ * FFmpeg 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 FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+/**
+ * @file
+ * Sega FILM (.cpk) file muxer
+ * @author Misty De Meo <misty at brew.sh>
+ *
+ * @see For more information regarding the Sega FILM file format, visit:
+ * http://wiki.multimedia.cx/index.php?title=Sega_FILM
+ */
+
+#include "libavutil/intreadwrite.h"
+#include "avformat.h"
+#include "internal.h"
+#include "avio_internal.h"
+
+typedef struct FILMPacket {
+ int audio;
+ int keyframe;
+ int32_t pts;
+ int32_t duration;
+ int32_t size;
+ int32_t index;
+ struct FILMPacket *next;
+} FILMPacket;
+
+typedef struct FILMOutputContext {
+ const AVClass *class;
+ int audio_index;
+ int video_index;
+ int64_t stab_pos;
+ FILMPacket *start;
+ FILMPacket *last;
+ int64_t packet_count;
+} FILMOutputContext;
+
+static int film_write_packet_to_header(AVFormatContext *format_context, FILMPacket *pkt)
+{
+ AVIOContext *pb = format_context->pb;
+ // The bits in these two 32-bit integers contain info about the contents of this sample
+ int32_t info1 = 0;
+ int32_t info2 = 0;
+
+ if (pkt->audio) {
+ // Always the same, carries no more information than "this is audio"
+ info1 = 0xFFFFFFFF;
+ info2 = 1;
+ } else {
+ info1 = pkt->pts;
+ info2 = pkt->duration;
+ // The top bit being set indicates a key frame
+ if (pkt->keyframe)
+ info1 |= (1 << 31);
+ }
+
+ // Write the 16-byte sample info packet to the STAB chunk in the header
+ avio_wb32(pb, pkt->index);
+ avio_wb32(pb, pkt->size);
+ avio_wb32(pb, info1);
+ avio_wb32(pb, info2);
+
+ return 0;
+}
+
+static int film_write_packet(AVFormatContext *format_context, AVPacket *pkt)
+{
+ FILMPacket *metadata;
+ AVIOContext *pb = format_context->pb;
+ FILMOutputContext *film = format_context->priv_data;
+ int encoded_buf_size = 0;
+
+ // Track the metadata used to write the header and add it to the linked list
+ metadata = av_mallocz(sizeof(FILMPacket));
+ if (!metadata)
+ return AVERROR(ENOMEM);
+ metadata->audio = pkt->stream_index == film->audio_index;
+ metadata->keyframe = pkt->flags & AV_PKT_FLAG_KEY;
+ metadata->pts = pkt->pts;
+ metadata->duration = pkt->duration;
+ metadata->size = pkt->size;
+ if (film->last == NULL) {
+ metadata->index = 0;
+ } else {
+ metadata->index = film->last->index + film->last->size;
+ film->last->next = metadata;
+ }
+ metadata->next = NULL;
+ if (film->start == NULL)
+ film->start = metadata;
+ film->packet_count++;
+ film->last = metadata;
+
+ /* Sega Cinepak has an extra two-byte header; write dummy data there,
+ * then adjust the cvid header to accommodate for the extra size */
+ if (!metadata->audio) {
+ encoded_buf_size = AV_RB24(&pkt->data[1]);
+ // Already Sega Cinepak, so no need to reformat the packets
+ if (encoded_buf_size != pkt->size && (pkt->size % encoded_buf_size) != 0) {
+ avio_write(pb, pkt->data, pkt->size);
+ } else {
+ /* In Sega Cinepak, the reported size in the Cinepak header is
+ * 8 bytes too short. However, the size in the STAB section of the header
+ * is correct, taking into account the extra two bytes. */
+ AV_WB24(&pkt->data[1], pkt->size - 8 + 2);
+ metadata->size += 2;
+ uint8_t padding[2] = {0, 0};
+
+ avio_write(pb, pkt->data, 10);
+ avio_write(pb, padding, 2);
+ avio_write(pb, &pkt->data[10], pkt->size - 10);
+ }
+ } else {
+ // Audio can just be written as-is
+ avio_write(pb, pkt->data, pkt->size);
+ }
+
+ return 0;
+}
+
+static int get_audio_codec_id(enum AVCodecID codec_id)
+{
+ // 0 (PCM) and 2 (ADX) are the only known values
+ switch (codec_id) {
+ case AV_CODEC_ID_PCM_S8_PLANAR:
+ case AV_CODEC_ID_PCM_S16BE_PLANAR:
+ return 0;
+ break;
+ case AV_CODEC_ID_ADPCM_ADX:
+ return 2;
+ break;
+ default:
+ return -1;
+ }
+}
+
+static int film_init(AVFormatContext *format_context)
+{
+ FILMOutputContext *film = format_context->priv_data;
+ film->audio_index = -1;
+ film->video_index = -1;
+ film->stab_pos = 0;
+ film->packet_count = 0;
+ film->start = NULL;
+ film->last = NULL;
+ AVStream *audio = NULL;
+
+ for (int i = 0; i < format_context->nb_streams; i++) {
+ AVStream *st = format_context->streams[i];
+ if (st->codecpar->codec_type == AVMEDIA_TYPE_AUDIO) {
+ if (film->audio_index > -1) {
+ av_log(format_context, AV_LOG_ERROR, "Sega FILM allows a maximum of one audio stream.\n");
+ return AVERROR(EINVAL);
+ }
+ film->audio_index = i;
+ audio = st;
+ }
+
+ if (st->codecpar->codec_type == AVMEDIA_TYPE_VIDEO) {
+ if (film->video_index > -1) {
+ av_log(format_context, AV_LOG_ERROR, "Sega FILM allows a maximum of one video stream.\n");
+ return AVERROR(EINVAL);
+ }
+ film->video_index = i;
+ }
+
+ if (film->video_index == -1) {
+ av_log(format_context, AV_LOG_ERROR, "No video stream present.\n");
+ return AVERROR(EINVAL);
+ }
+ }
+
+ if (audio != NULL && get_audio_codec_id(audio->codecpar->codec_id) < 0) {
+ av_log(format_context, AV_LOG_ERROR, "Incompatible audio stream format.\n");
+ return AVERROR(EINVAL);
+ }
+
+ return 0;
+}
+
+static int shift_data(AVFormatContext *format_context, int64_t shift_size)
+{
+ int ret = 0;
+ int64_t pos, pos_end = avio_tell(format_context->pb);
+ uint8_t *buf, *read_buf[2];
+ int read_buf_id = 0;
+ int read_size[2];
+ AVIOContext *read_pb;
+
+ buf = av_malloc(shift_size * 2);
+ if (!buf)
+ return AVERROR(ENOMEM);
+ read_buf[0] = buf;
+ read_buf[1] = buf + shift_size;
+
+ /* Write the header at the beginning of the file, shifting all content as necessary;
+ * based on the approach used by MOV faststart. */
+ avio_flush(format_context->pb);
+ ret = format_context->io_open(format_context, &read_pb, format_context->url, AVIO_FLAG_READ, NULL);
+ if (ret < 0) {
+ av_log(format_context, AV_LOG_ERROR, "Unable to re-open %s output file to "
+ "write the header\n", format_context->url);
+ av_free(buf);
+ return ret;
+ }
+
+ /* mark the end of the shift to up to the last data we wrote, and get ready
+ * for writing */
+ pos_end = avio_tell(format_context->pb);
+ avio_seek(format_context->pb, shift_size, SEEK_SET);
+
+ /* start reading at where the new header will be placed */
+ avio_seek(read_pb, 0, SEEK_SET);
+ pos = avio_tell(read_pb);
+
+#define READ_BLOCK do { \
+ read_size[read_buf_id] = avio_read(read_pb, read_buf[read_buf_id], shift_size); \
+ read_buf_id ^= 1; \
+} while (0)
+
+ /* shift data by chunk of at most shift_size */
+ READ_BLOCK;
+ do {
+ int n;
+ READ_BLOCK;
+ n = read_size[read_buf_id];
+ if (n <= 0)
+ break;
+ avio_write(format_context->pb, read_buf[read_buf_id], n);
+ pos += n;
+ } while (pos < pos_end);
+ ff_format_io_close(format_context, &read_pb);
+
+ av_free(buf);
+ return 0;
+}
+
+static int film_write_header(AVFormatContext *format_context)
+{
+ int ret = 0;
+ int64_t sample_table_size, stabsize, headersize;
+ int8_t audio_codec;
+ AVIOContext *pb = format_context->pb;
+ FILMOutputContext *film = format_context->priv_data;
+ FILMPacket *prev, *packet;
+ AVStream *audio = NULL;
+ AVStream *video = NULL;
+
+ /* Calculate how much we need to reserve for the header;
+ * this is the amount the rest of the data will be shifted up by. */
+ sample_table_size = film->packet_count * 16;
+ stabsize = 16 + sample_table_size;
+ headersize = 16 + // FILM header base
+ 32 + // FDSC chunk
+ stabsize;
+
+ ret = shift_data(format_context, headersize);
+ if (ret < 0)
+ return ret;
+ // Seek back to the beginning to start writing the header now
+ avio_seek(pb, 0, SEEK_SET);
+
+ if (film->audio_index > -1)
+ audio = format_context->streams[film->audio_index];
+ if (film->video_index > -1)
+ video = format_context->streams[film->video_index];
+
+ if (audio != NULL) {
+ audio_codec = get_audio_codec_id(audio->codecpar->codec_id);
+ if (audio_codec < 0) {
+ av_log(format_context, AV_LOG_ERROR, "Incompatible audio stream format.\n");
+ return AVERROR(EINVAL);
+ }
+ }
+
+ // First, write the FILM header; this is very simple
+
+ ffio_wfourcc(pb, "FILM");
+ avio_wb32(pb, 48 + stabsize);
+ /* This seems to be okay to hardcode, since this muxer targets 1.09 features;
+ * videos produced by this muxer are readable by 1.08 and lower players. */
+ ffio_wfourcc(pb, "1.09");
+ // I have no idea what this field does, might be reserved
+ avio_wb32(pb, 0);
+
+ // Next write the FDSC (file description) chunk
+ ffio_wfourcc(pb, "FDSC");
+ avio_wb32(pb, 0x20); // Size of FDSC chunk
+ // TODO stop hardcoding this if support for another codec is added
+ ffio_wfourcc(pb, "cvid");
+ avio_wb32(pb, video->codecpar->height);
+ avio_wb32(pb, video->codecpar->width);
+ avio_w8(pb, 24); // Bits per pixel - observed to always be 24
+
+ if (audio != NULL) {
+ avio_w8(pb, audio->codecpar->channels); // Audio channels
+ avio_w8(pb, audio->codecpar->bits_per_coded_sample); // Audio bit depth
+ avio_w8(pb, audio_codec); // Compression - 0 is PCM, 2 is ADX
+ avio_wb16(pb, audio->codecpar->sample_rate); // Audio sampling rate
+ } else {
+ // Set all these fields to 0 if there's no audio
+ avio_w8(pb, 0);
+ avio_w8(pb, 0);
+ avio_w8(pb, 0);
+ avio_wb16(pb, 0);
+ }
+
+ // I have no idea what this pair of fields does either, might be reserved
+ avio_wb32(pb, 0);
+ avio_wb16(pb, 0);
+
+ // Finally, write the STAB (sample table) chunk
+ ffio_wfourcc(pb, "STAB");
+ avio_wb32(pb, 16 + (film->packet_count * 16));
+ /* Framerate base frequency. Here we're assuming that the frame rate is even.
+ * In real world Sega FILM files, there are usually a couple of approaches:
+ * a) framerate base frequency is the same as the framerate, and ticks
+ * increment by 1 every frame, or
+ * b) framerate base frequency is a much larger number, and ticks
+ * increment by larger steps every frame.
+ * The latter occurs even in cases where the frame rate is even; for example, in
+ * Lunar: Silver Star Story, the base frequency is 600 and each frame, the ticks
+ * are incremented by 25 for an evenly spaced framerate of 24fps. */
+ avio_wb32(pb, av_q2d(av_inv_q(video->time_base)));
+
+ avio_wb32(pb, film->packet_count);
+
+ avio_flush(pb);
+
+ // Finally, write out each packet's data to the header
+ packet = film->start;
+ while (packet != NULL) {
+ film_write_packet_to_header(format_context, packet);
+ prev = packet;
+ packet = packet->next;
+ av_freep(&prev);
+ }
+
+ return 0;
+}
+
+static const AVClass film_muxer_class = {
+ .class_name = "Sega FILM muxer",
+ .item_name = av_default_item_name,
+ .version = LIBAVUTIL_VERSION_INT,
+};
+
+AVOutputFormat ff_segafilm_muxer = {
+ .name = "film_cpk",
+ .long_name = NULL_IF_CONFIG_SMALL("Sega FILM / CPK"),
+ .extensions = "cpk",
+ .priv_data_size = sizeof(FILMOutputContext),
+ .audio_codec = AV_CODEC_ID_PCM_S16BE_PLANAR,
+ .video_codec = AV_CODEC_ID_CINEPAK,
+ .init = film_init,
+ .write_trailer = film_write_header,
+ .write_packet = film_write_packet,
+ .priv_class = &film_muxer_class,
+};
diff --git a/libavformat/version.h b/libavformat/version.h
index e28a9e7dfe..b55d51c1b7 100644
--- a/libavformat/version.h
+++ b/libavformat/version.h
@@ -32,7 +32,7 @@
// Major bumping may affect Ticket5467, 5421, 5451(compatibility with Chromium)
// Also please add any ticket numbers that you believe might be affected here
#define LIBAVFORMAT_VERSION_MAJOR 58
-#define LIBAVFORMAT_VERSION_MINOR 10
+#define LIBAVFORMAT_VERSION_MINOR 11
#define LIBAVFORMAT_VERSION_MICRO 100
#define LIBAVFORMAT_VERSION_INT AV_VERSION_INT(LIBAVFORMAT_VERSION_MAJOR, \
--
2.16.2
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