| /* |
| * Sega FILM Format (CPK) Muxer |
| * Copyright (C) 2003 The FFmpeg project |
| * Copyright (C) 2018 Misty De Meo |
| * |
| * 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; |
| AVIOContext *pb = format_context->pb; |
| FILMOutputContext *film = format_context->priv_data; |
| int encoded_buf_size = 0; |
| enum AVCodecID codec_id; |
| |
| /* 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; |
| |
| codec_id = format_context->streams[pkt->stream_index]->codecpar->codec_id; |
| |
| /* Sega Cinepak has an extra two-byte header; write dummy data there, |
| * then adjust the cvid header to accommodate for the extra size */ |
| if (codec_id == AV_CODEC_ID_CINEPAK) { |
| 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 { |
| uint8_t padding[2] = {0, 0}; |
| /* 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; |
| |
| avio_write(pb, pkt->data, 10); |
| avio_write(pb, padding, 2); |
| avio_write(pb, &pkt->data[10], pkt->size - 10); |
| } |
| } else { |
| /* Other formats 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) |
| { |
| AVStream *audio = NULL; |
| 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; |
| |
| 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); |
| } |
| } |
| |
| if (video->codecpar->format != AV_PIX_FMT_RGB24) { |
| av_log(format_context, AV_LOG_ERROR, "Pixel format must be rgb24.\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 */ |
| |
| /* The only two supported codecs; raw video is rare */ |
| switch (video->codecpar->codec_id) { |
| case AV_CODEC_ID_CINEPAK: |
| ffio_wfourcc(pb, "cvid"); |
| break; |
| case AV_CODEC_ID_RAWVIDEO: |
| ffio_wfourcc(pb, "raw "); |
| break; |
| default: |
| av_log(format_context, AV_LOG_ERROR, "Incompatible video stream format.\n"); |
| return AVERROR(EINVAL); |
| } |
| |
| 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, |
| }; |
