| /* |
| * Psygnosis YOP demuxer |
| * |
| * Copyright (C) 2010 Mohamed Naufal Basheer <naufal11@gmail.com> |
| * derived from the code by |
| * Copyright (C) 2009 Thomas P. Higdon <thomas.p.higdon@gmail.com> |
| * |
| * 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 |
| */ |
| |
| #include "libavutil/channel_layout.h" |
| #include "libavutil/intreadwrite.h" |
| #include "avformat.h" |
| #include "internal.h" |
| |
| typedef struct yop_dec_context { |
| AVPacket video_packet; |
| |
| int odd_frame; |
| int frame_size; |
| int audio_block_length; |
| int palette_size; |
| } YopDecContext; |
| |
| static int yop_probe(const AVProbeData *probe_packet) |
| { |
| if (AV_RB16(probe_packet->buf) == AV_RB16("YO") && |
| probe_packet->buf[2]<10 && |
| probe_packet->buf[3]<10 && |
| probe_packet->buf[6] && |
| probe_packet->buf[7] && |
| !(probe_packet->buf[8] & 1) && |
| !(probe_packet->buf[10] & 1) && |
| AV_RL16(probe_packet->buf + 12 + 6) >= 920 && |
| AV_RL16(probe_packet->buf + 12 + 6) < probe_packet->buf[12] * 3 + 4 + probe_packet->buf[7] * 2048 |
| ) |
| return AVPROBE_SCORE_MAX * 3 / 4; |
| |
| return 0; |
| } |
| |
| static int yop_read_header(AVFormatContext *s) |
| { |
| YopDecContext *yop = s->priv_data; |
| AVIOContext *pb = s->pb; |
| |
| AVCodecParameters *audio_par, *video_par; |
| AVStream *audio_stream, *video_stream; |
| |
| int frame_rate, ret; |
| |
| audio_stream = avformat_new_stream(s, NULL); |
| video_stream = avformat_new_stream(s, NULL); |
| if (!audio_stream || !video_stream) |
| return AVERROR(ENOMEM); |
| |
| // Audio |
| audio_par = audio_stream->codecpar; |
| audio_par->codec_type = AVMEDIA_TYPE_AUDIO; |
| audio_par->codec_id = AV_CODEC_ID_ADPCM_IMA_APC; |
| audio_par->channels = 1; |
| audio_par->channel_layout = AV_CH_LAYOUT_MONO; |
| audio_par->sample_rate = 22050; |
| |
| // Video |
| video_par = video_stream->codecpar; |
| video_par->codec_type = AVMEDIA_TYPE_VIDEO; |
| video_par->codec_id = AV_CODEC_ID_YOP; |
| |
| avio_skip(pb, 6); |
| |
| frame_rate = avio_r8(pb); |
| yop->frame_size = avio_r8(pb) * 2048; |
| video_par->width = avio_rl16(pb); |
| video_par->height = avio_rl16(pb); |
| |
| video_stream->sample_aspect_ratio = (AVRational){1, 2}; |
| |
| ret = ff_get_extradata(s, video_par, pb, 8); |
| if (ret < 0) |
| return ret; |
| |
| yop->palette_size = video_par->extradata[0] * 3 + 4; |
| yop->audio_block_length = AV_RL16(video_par->extradata + 6); |
| |
| video_par->bit_rate = 8 * (yop->frame_size - yop->audio_block_length) * frame_rate; |
| |
| // 1840 samples per frame, 1 nibble per sample; hence 1840/2 = 920 |
| if (yop->audio_block_length < 920 || |
| yop->audio_block_length + yop->palette_size >= yop->frame_size) { |
| av_log(s, AV_LOG_ERROR, "YOP has invalid header\n"); |
| return AVERROR_INVALIDDATA; |
| } |
| |
| avio_seek(pb, 2048, SEEK_SET); |
| |
| avpriv_set_pts_info(video_stream, 32, 1, frame_rate); |
| |
| return 0; |
| } |
| |
| static int yop_read_packet(AVFormatContext *s, AVPacket *pkt) |
| { |
| YopDecContext *yop = s->priv_data; |
| AVIOContext *pb = s->pb; |
| |
| int ret; |
| int actual_video_data_size = yop->frame_size - |
| yop->audio_block_length - yop->palette_size; |
| |
| yop->video_packet.stream_index = 1; |
| |
| if (yop->video_packet.data) { |
| av_packet_move_ref(pkt, &yop->video_packet); |
| pkt->data[0] = yop->odd_frame; |
| pkt->flags |= AV_PKT_FLAG_KEY; |
| yop->odd_frame ^= 1; |
| return 0; |
| } |
| ret = av_new_packet(&yop->video_packet, |
| yop->frame_size - yop->audio_block_length); |
| if (ret < 0) |
| return ret; |
| |
| yop->video_packet.pos = avio_tell(pb); |
| |
| ret = avio_read(pb, yop->video_packet.data, yop->palette_size); |
| if (ret < 0) { |
| goto err_out; |
| }else if (ret < yop->palette_size) { |
| ret = AVERROR_EOF; |
| goto err_out; |
| } |
| |
| ret = av_get_packet(pb, pkt, 920); |
| if (ret < 0) |
| goto err_out; |
| |
| // Set position to the start of the frame |
| pkt->pos = yop->video_packet.pos; |
| |
| avio_skip(pb, yop->audio_block_length - ret); |
| |
| ret = avio_read(pb, yop->video_packet.data + yop->palette_size, |
| actual_video_data_size); |
| if (ret < 0) |
| goto err_out; |
| else if (ret < actual_video_data_size) |
| av_shrink_packet(&yop->video_packet, yop->palette_size + ret); |
| |
| // Arbitrarily return the audio data first |
| return 0; |
| |
| err_out: |
| av_packet_unref(&yop->video_packet); |
| return ret; |
| } |
| |
| static int yop_read_close(AVFormatContext *s) |
| { |
| YopDecContext *yop = s->priv_data; |
| av_packet_unref(&yop->video_packet); |
| return 0; |
| } |
| |
| static int yop_read_seek(AVFormatContext *s, int stream_index, |
| int64_t timestamp, int flags) |
| { |
| YopDecContext *yop = s->priv_data; |
| int64_t frame_pos, pos_min, pos_max; |
| int frame_count; |
| |
| if (!stream_index) |
| return -1; |
| |
| pos_min = s->internal->data_offset; |
| pos_max = avio_size(s->pb) - yop->frame_size; |
| frame_count = (pos_max - pos_min) / yop->frame_size; |
| |
| timestamp = FFMAX(0, FFMIN(frame_count, timestamp)); |
| |
| frame_pos = timestamp * yop->frame_size + pos_min; |
| |
| if (avio_seek(s->pb, frame_pos, SEEK_SET) < 0) |
| return -1; |
| |
| av_packet_unref(&yop->video_packet); |
| yop->odd_frame = timestamp & 1; |
| |
| return 0; |
| } |
| |
| AVInputFormat ff_yop_demuxer = { |
| .name = "yop", |
| .long_name = NULL_IF_CONFIG_SMALL("Psygnosis YOP"), |
| .priv_data_size = sizeof(YopDecContext), |
| .read_probe = yop_probe, |
| .read_header = yop_read_header, |
| .read_packet = yop_read_packet, |
| .read_close = yop_read_close, |
| .read_seek = yop_read_seek, |
| .extensions = "yop", |
| .flags = AVFMT_GENERIC_INDEX, |
| }; |