yading@11: /* yading@11: * Psygnosis YOP demuxer yading@11: * yading@11: * Copyright (C) 2010 Mohamed Naufal Basheer yading@11: * derived from the code by yading@11: * Copyright (C) 2009 Thomas P. Higdon yading@11: * yading@11: * This file is part of FFmpeg. yading@11: * yading@11: * FFmpeg is free software; you can redistribute it and/or yading@11: * modify it under the terms of the GNU Lesser General Public yading@11: * License as published by the Free Software Foundation; either yading@11: * version 2.1 of the License, or (at your option) any later version. yading@11: * yading@11: * FFmpeg is distributed in the hope that it will be useful, yading@11: * but WITHOUT ANY WARRANTY; without even the implied warranty of yading@11: * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU yading@11: * Lesser General Public License for more details. yading@11: * yading@11: * You should have received a copy of the GNU Lesser General Public yading@11: * License along with FFmpeg; if not, write to the Free Software yading@11: * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA yading@11: */ yading@11: yading@11: #include "libavutil/channel_layout.h" yading@11: #include "libavutil/intreadwrite.h" yading@11: #include "avformat.h" yading@11: #include "internal.h" yading@11: yading@11: typedef struct yop_dec_context { yading@11: AVPacket video_packet; yading@11: yading@11: int odd_frame; yading@11: int frame_size; yading@11: int audio_block_length; yading@11: int palette_size; yading@11: } YopDecContext; yading@11: yading@11: static int yop_probe(AVProbeData *probe_packet) yading@11: { yading@11: if (AV_RB16(probe_packet->buf) == AV_RB16("YO") && yading@11: probe_packet->buf[2]<10 && yading@11: probe_packet->buf[3]<10 && yading@11: probe_packet->buf[6] && yading@11: probe_packet->buf[7] && yading@11: !(probe_packet->buf[8] & 1) && yading@11: !(probe_packet->buf[10] & 1) && yading@11: AV_RL16(probe_packet->buf + 12 + 6) >= 920 && yading@11: AV_RL16(probe_packet->buf + 12 + 6) < probe_packet->buf[12] * 3 + 4 + probe_packet->buf[7] * 2048 yading@11: ) yading@11: return AVPROBE_SCORE_MAX * 3 / 4; yading@11: yading@11: return 0; yading@11: } yading@11: yading@11: static int yop_read_header(AVFormatContext *s) yading@11: { yading@11: YopDecContext *yop = s->priv_data; yading@11: AVIOContext *pb = s->pb; yading@11: yading@11: AVCodecContext *audio_dec, *video_dec; yading@11: AVStream *audio_stream, *video_stream; yading@11: yading@11: int frame_rate, ret; yading@11: yading@11: audio_stream = avformat_new_stream(s, NULL); yading@11: video_stream = avformat_new_stream(s, NULL); yading@11: if (!audio_stream || !video_stream) yading@11: return AVERROR(ENOMEM); yading@11: yading@11: // Extra data that will be passed to the decoder yading@11: video_stream->codec->extradata_size = 8; yading@11: yading@11: video_stream->codec->extradata = av_mallocz(video_stream->codec->extradata_size + yading@11: FF_INPUT_BUFFER_PADDING_SIZE); yading@11: yading@11: if (!video_stream->codec->extradata) yading@11: return AVERROR(ENOMEM); yading@11: yading@11: // Audio yading@11: audio_dec = audio_stream->codec; yading@11: audio_dec->codec_type = AVMEDIA_TYPE_AUDIO; yading@11: audio_dec->codec_id = AV_CODEC_ID_ADPCM_IMA_APC; yading@11: audio_dec->channels = 1; yading@11: audio_dec->channel_layout = AV_CH_LAYOUT_MONO; yading@11: audio_dec->sample_rate = 22050; yading@11: yading@11: // Video yading@11: video_dec = video_stream->codec; yading@11: video_dec->codec_type = AVMEDIA_TYPE_VIDEO; yading@11: video_dec->codec_id = AV_CODEC_ID_YOP; yading@11: yading@11: avio_skip(pb, 6); yading@11: yading@11: frame_rate = avio_r8(pb); yading@11: yop->frame_size = avio_r8(pb) * 2048; yading@11: video_dec->width = avio_rl16(pb); yading@11: video_dec->height = avio_rl16(pb); yading@11: yading@11: video_stream->sample_aspect_ratio = (AVRational){1, 2}; yading@11: yading@11: ret = avio_read(pb, video_dec->extradata, 8); yading@11: if (ret < 8) yading@11: return ret < 0 ? ret : AVERROR_EOF; yading@11: yading@11: yop->palette_size = video_dec->extradata[0] * 3 + 4; yading@11: yop->audio_block_length = AV_RL16(video_dec->extradata + 6); yading@11: yading@11: video_dec->bit_rate = 8 * (yop->frame_size - yop->audio_block_length) * frame_rate; yading@11: yading@11: // 1840 samples per frame, 1 nibble per sample; hence 1840/2 = 920 yading@11: if (yop->audio_block_length < 920 || yading@11: yop->audio_block_length + yop->palette_size >= yop->frame_size) { yading@11: av_log(s, AV_LOG_ERROR, "YOP has invalid header\n"); yading@11: return AVERROR_INVALIDDATA; yading@11: } yading@11: yading@11: avio_seek(pb, 2048, SEEK_SET); yading@11: yading@11: avpriv_set_pts_info(video_stream, 32, 1, frame_rate); yading@11: yading@11: return 0; yading@11: } yading@11: yading@11: static int yop_read_packet(AVFormatContext *s, AVPacket *pkt) yading@11: { yading@11: YopDecContext *yop = s->priv_data; yading@11: AVIOContext *pb = s->pb; yading@11: yading@11: int ret; yading@11: int actual_video_data_size = yop->frame_size - yading@11: yop->audio_block_length - yop->palette_size; yading@11: yading@11: yop->video_packet.stream_index = 1; yading@11: yading@11: if (yop->video_packet.data) { yading@11: *pkt = yop->video_packet; yading@11: memset(&yop->video_packet, 0, sizeof(yop->video_packet)); yading@11: pkt->data[0] = yop->odd_frame; yading@11: pkt->flags |= AV_PKT_FLAG_KEY; yading@11: yop->odd_frame ^= 1; yading@11: return pkt->size; yading@11: } yading@11: ret = av_new_packet(&yop->video_packet, yading@11: yop->frame_size - yop->audio_block_length); yading@11: if (ret < 0) yading@11: return ret; yading@11: yading@11: yop->video_packet.pos = avio_tell(pb); yading@11: yading@11: ret = avio_read(pb, yop->video_packet.data, yop->palette_size); yading@11: if (ret < 0) { yading@11: goto err_out; yading@11: }else if (ret < yop->palette_size) { yading@11: ret = AVERROR_EOF; yading@11: goto err_out; yading@11: } yading@11: yading@11: ret = av_get_packet(pb, pkt, 920); yading@11: if (ret < 0) yading@11: goto err_out; yading@11: yading@11: // Set position to the start of the frame yading@11: pkt->pos = yop->video_packet.pos; yading@11: yading@11: avio_skip(pb, yop->audio_block_length - ret); yading@11: yading@11: ret = avio_read(pb, yop->video_packet.data + yop->palette_size, yading@11: actual_video_data_size); yading@11: if (ret < 0) yading@11: goto err_out; yading@11: else if (ret < actual_video_data_size) yading@11: av_shrink_packet(&yop->video_packet, yop->palette_size + ret); yading@11: yading@11: // Arbitrarily return the audio data first yading@11: return yop->audio_block_length; yading@11: yading@11: err_out: yading@11: av_free_packet(&yop->video_packet); yading@11: return ret; yading@11: } yading@11: yading@11: static int yop_read_close(AVFormatContext *s) yading@11: { yading@11: YopDecContext *yop = s->priv_data; yading@11: av_free_packet(&yop->video_packet); yading@11: return 0; yading@11: } yading@11: yading@11: static int yop_read_seek(AVFormatContext *s, int stream_index, yading@11: int64_t timestamp, int flags) yading@11: { yading@11: YopDecContext *yop = s->priv_data; yading@11: int64_t frame_pos, pos_min, pos_max; yading@11: int frame_count; yading@11: yading@11: if (!stream_index) yading@11: return -1; yading@11: yading@11: pos_min = s->data_offset; yading@11: pos_max = avio_size(s->pb) - yop->frame_size; yading@11: frame_count = (pos_max - pos_min) / yop->frame_size; yading@11: yading@11: timestamp = FFMAX(0, FFMIN(frame_count, timestamp)); yading@11: yading@11: frame_pos = timestamp * yop->frame_size + pos_min; yading@11: yading@11: if (avio_seek(s->pb, frame_pos, SEEK_SET) < 0) yading@11: return -1; yading@11: yading@11: av_free_packet(&yop->video_packet); yading@11: yop->odd_frame = timestamp & 1; yading@11: yading@11: return 0; yading@11: } yading@11: yading@11: AVInputFormat ff_yop_demuxer = { yading@11: .name = "yop", yading@11: .long_name = NULL_IF_CONFIG_SMALL("Psygnosis YOP"), yading@11: .priv_data_size = sizeof(YopDecContext), yading@11: .read_probe = yop_probe, yading@11: .read_header = yop_read_header, yading@11: .read_packet = yop_read_packet, yading@11: .read_close = yop_read_close, yading@11: .read_seek = yop_read_seek, yading@11: .extensions = "yop", yading@11: .flags = AVFMT_GENERIC_INDEX, yading@11: };