Message ID | 20180322054631.36964-2-misty@brew.sh |
---|---|
State | Superseded |
Headers | show |
On 3/22/18, misty@brew.sh <misty@brew.sh> wrote: > From: Misty De Meo <mistydemeo@gmail.com> > > --- > Changelog | 1 + > libavformat/Makefile | 1 + > libavformat/allformats.c | 1 + > libavformat/segafilmenc.c | 380 > ++++++++++++++++++++++++++++++++++++++++++++++ > 4 files changed, 383 insertions(+) > 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/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..cc0e21d4d3 > --- /dev/null > +++ b/libavformat/segafilmenc.c > @@ -0,0 +1,380 @@ > +/* > + * Cinepak Video Decoder > + * 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@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 = av_mallocz(sizeof(FILMPacket)); > + if (!metadata) > + return AVERROR(ENOMEM); Do not mix initializations and calling other functions. Here and in others places. > + 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->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: > + 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 stabstart_pos, 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); Have you checked that all audio codecs supported her do actually work? > + } > + } > + > + // 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 > + stabstart_pos = avio_tell(pb); > + 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) > + { Put '{' above. > + 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, > +}; > -- > 2.16.2 Generally looks pretty good.
On Wed, Mar 21, 2018 at 10:46:31PM -0700, misty@brew.sh wrote: > From: Misty De Meo <mistydemeo@gmail.com> [...] > +static int film_write_header(AVFormatContext *format_context) > +{ > + int ret = 0; > + int64_t stabstart_pos, 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 > + stabstart_pos = avio_tell(pb); this is set but never used [...]
From: Misty De Meo <mistydemeo@gmail.com> > Just move allocation after all declarations. OK, changed. > Do you check that this condition is set in code? > > I mean, if user set codec for wrong case. Oh, good point. I thought about this, and then realized that for mono audio, there is no difference between planar and non-planar. If the muxer only accepts planar then it'll work in both cases and there doesn't have to be a special check. That also matches the behaviour of the demuxer, which marks streams as planar regardless of channel layout. > this is set but never used Good catch - removed. Left over from an older version of the header generation. Misty De Meo (1): Add Sega FILM muxer Changelog | 1 + libavformat/Makefile | 1 + libavformat/allformats.c | 1 + libavformat/segafilmenc.c | 377 ++++++++++++++++++++++++++++++++++++++++++++++ 4 files changed, 380 insertions(+) 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/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..cc0e21d4d3 --- /dev/null +++ b/libavformat/segafilmenc.c @@ -0,0 +1,380 @@ +/* + * Cinepak Video Decoder + * 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@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 = av_mallocz(sizeof(FILMPacket)); + if (!metadata) + return AVERROR(ENOMEM); + 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->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: + 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 stabstart_pos, 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 + stabstart_pos = avio_tell(pb); + 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, +};
From: Misty De Meo <mistydemeo@gmail.com> --- Changelog | 1 + libavformat/Makefile | 1 + libavformat/allformats.c | 1 + libavformat/segafilmenc.c | 380 ++++++++++++++++++++++++++++++++++++++++++++++ 4 files changed, 383 insertions(+) create mode 100644 libavformat/segafilmenc.c