| 1 | /* |
| 2 | * Psygnosis YOP demuxer |
| 3 | * |
| 4 | * Copyright (C) 2010 Mohamed Naufal Basheer <naufal11@gmail.com> |
| 5 | * derived from the code by |
| 6 | * Copyright (C) 2009 Thomas P. Higdon <thomas.p.higdon@gmail.com> |
| 7 | * |
| 8 | * This file is part of FFmpeg. |
| 9 | * |
| 10 | * FFmpeg is free software; you can redistribute it and/or |
| 11 | * modify it under the terms of the GNU Lesser General Public |
| 12 | * License as published by the Free Software Foundation; either |
| 13 | * version 2.1 of the License, or (at your option) any later version. |
| 14 | * |
| 15 | * FFmpeg is distributed in the hope that it will be useful, |
| 16 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 17 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 18 | * Lesser General Public License for more details. |
| 19 | * |
| 20 | * You should have received a copy of the GNU Lesser General Public |
| 21 | * License along with FFmpeg; if not, write to the Free Software |
| 22 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
| 23 | */ |
| 24 | |
| 25 | #include "libavutil/channel_layout.h" |
| 26 | #include "libavutil/intreadwrite.h" |
| 27 | #include "avformat.h" |
| 28 | #include "internal.h" |
| 29 | |
| 30 | typedef struct yop_dec_context { |
| 31 | AVPacket video_packet; |
| 32 | |
| 33 | int odd_frame; |
| 34 | int frame_size; |
| 35 | int audio_block_length; |
| 36 | int palette_size; |
| 37 | } YopDecContext; |
| 38 | |
| 39 | static int yop_probe(AVProbeData *probe_packet) |
| 40 | { |
| 41 | if (AV_RB16(probe_packet->buf) == AV_RB16("YO") && |
| 42 | probe_packet->buf[2]<10 && |
| 43 | probe_packet->buf[3]<10 && |
| 44 | probe_packet->buf[6] && |
| 45 | probe_packet->buf[7] && |
| 46 | !(probe_packet->buf[8] & 1) && |
| 47 | !(probe_packet->buf[10] & 1) && |
| 48 | AV_RL16(probe_packet->buf + 12 + 6) >= 920 && |
| 49 | AV_RL16(probe_packet->buf + 12 + 6) < probe_packet->buf[12] * 3 + 4 + probe_packet->buf[7] * 2048 |
| 50 | ) |
| 51 | return AVPROBE_SCORE_MAX * 3 / 4; |
| 52 | |
| 53 | return 0; |
| 54 | } |
| 55 | |
| 56 | static int yop_read_header(AVFormatContext *s) |
| 57 | { |
| 58 | YopDecContext *yop = s->priv_data; |
| 59 | AVIOContext *pb = s->pb; |
| 60 | |
| 61 | AVCodecContext *audio_dec, *video_dec; |
| 62 | AVStream *audio_stream, *video_stream; |
| 63 | |
| 64 | int frame_rate, ret; |
| 65 | |
| 66 | audio_stream = avformat_new_stream(s, NULL); |
| 67 | video_stream = avformat_new_stream(s, NULL); |
| 68 | if (!audio_stream || !video_stream) |
| 69 | return AVERROR(ENOMEM); |
| 70 | |
| 71 | // Extra data that will be passed to the decoder |
| 72 | if (ff_alloc_extradata(video_stream->codec, 8)) |
| 73 | return AVERROR(ENOMEM); |
| 74 | |
| 75 | // Audio |
| 76 | audio_dec = audio_stream->codec; |
| 77 | audio_dec->codec_type = AVMEDIA_TYPE_AUDIO; |
| 78 | audio_dec->codec_id = AV_CODEC_ID_ADPCM_IMA_APC; |
| 79 | audio_dec->channels = 1; |
| 80 | audio_dec->channel_layout = AV_CH_LAYOUT_MONO; |
| 81 | audio_dec->sample_rate = 22050; |
| 82 | |
| 83 | // Video |
| 84 | video_dec = video_stream->codec; |
| 85 | video_dec->codec_type = AVMEDIA_TYPE_VIDEO; |
| 86 | video_dec->codec_id = AV_CODEC_ID_YOP; |
| 87 | |
| 88 | avio_skip(pb, 6); |
| 89 | |
| 90 | frame_rate = avio_r8(pb); |
| 91 | yop->frame_size = avio_r8(pb) * 2048; |
| 92 | video_dec->width = avio_rl16(pb); |
| 93 | video_dec->height = avio_rl16(pb); |
| 94 | |
| 95 | video_stream->sample_aspect_ratio = (AVRational){1, 2}; |
| 96 | |
| 97 | ret = avio_read(pb, video_dec->extradata, 8); |
| 98 | if (ret < 8) |
| 99 | return ret < 0 ? ret : AVERROR_EOF; |
| 100 | |
| 101 | yop->palette_size = video_dec->extradata[0] * 3 + 4; |
| 102 | yop->audio_block_length = AV_RL16(video_dec->extradata + 6); |
| 103 | |
| 104 | video_dec->bit_rate = 8 * (yop->frame_size - yop->audio_block_length) * frame_rate; |
| 105 | |
| 106 | // 1840 samples per frame, 1 nibble per sample; hence 1840/2 = 920 |
| 107 | if (yop->audio_block_length < 920 || |
| 108 | yop->audio_block_length + yop->palette_size >= yop->frame_size) { |
| 109 | av_log(s, AV_LOG_ERROR, "YOP has invalid header\n"); |
| 110 | return AVERROR_INVALIDDATA; |
| 111 | } |
| 112 | |
| 113 | avio_seek(pb, 2048, SEEK_SET); |
| 114 | |
| 115 | avpriv_set_pts_info(video_stream, 32, 1, frame_rate); |
| 116 | |
| 117 | return 0; |
| 118 | } |
| 119 | |
| 120 | static int yop_read_packet(AVFormatContext *s, AVPacket *pkt) |
| 121 | { |
| 122 | YopDecContext *yop = s->priv_data; |
| 123 | AVIOContext *pb = s->pb; |
| 124 | |
| 125 | int ret; |
| 126 | int actual_video_data_size = yop->frame_size - |
| 127 | yop->audio_block_length - yop->palette_size; |
| 128 | |
| 129 | yop->video_packet.stream_index = 1; |
| 130 | |
| 131 | if (yop->video_packet.data) { |
| 132 | *pkt = yop->video_packet; |
| 133 | yop->video_packet.data = NULL; |
| 134 | yop->video_packet.buf = NULL; |
| 135 | #if FF_API_DESTRUCT_PACKET |
| 136 | FF_DISABLE_DEPRECATION_WARNINGS |
| 137 | yop->video_packet.destruct = NULL; |
| 138 | FF_ENABLE_DEPRECATION_WARNINGS |
| 139 | #endif |
| 140 | yop->video_packet.size = 0; |
| 141 | pkt->data[0] = yop->odd_frame; |
| 142 | pkt->flags |= AV_PKT_FLAG_KEY; |
| 143 | yop->odd_frame ^= 1; |
| 144 | return pkt->size; |
| 145 | } |
| 146 | ret = av_new_packet(&yop->video_packet, |
| 147 | yop->frame_size - yop->audio_block_length); |
| 148 | if (ret < 0) |
| 149 | return ret; |
| 150 | |
| 151 | yop->video_packet.pos = avio_tell(pb); |
| 152 | |
| 153 | ret = avio_read(pb, yop->video_packet.data, yop->palette_size); |
| 154 | if (ret < 0) { |
| 155 | goto err_out; |
| 156 | }else if (ret < yop->palette_size) { |
| 157 | ret = AVERROR_EOF; |
| 158 | goto err_out; |
| 159 | } |
| 160 | |
| 161 | ret = av_get_packet(pb, pkt, 920); |
| 162 | if (ret < 0) |
| 163 | goto err_out; |
| 164 | |
| 165 | // Set position to the start of the frame |
| 166 | pkt->pos = yop->video_packet.pos; |
| 167 | |
| 168 | avio_skip(pb, yop->audio_block_length - ret); |
| 169 | |
| 170 | ret = avio_read(pb, yop->video_packet.data + yop->palette_size, |
| 171 | actual_video_data_size); |
| 172 | if (ret < 0) |
| 173 | goto err_out; |
| 174 | else if (ret < actual_video_data_size) |
| 175 | av_shrink_packet(&yop->video_packet, yop->palette_size + ret); |
| 176 | |
| 177 | // Arbitrarily return the audio data first |
| 178 | return yop->audio_block_length; |
| 179 | |
| 180 | err_out: |
| 181 | av_free_packet(&yop->video_packet); |
| 182 | return ret; |
| 183 | } |
| 184 | |
| 185 | static int yop_read_close(AVFormatContext *s) |
| 186 | { |
| 187 | YopDecContext *yop = s->priv_data; |
| 188 | av_free_packet(&yop->video_packet); |
| 189 | return 0; |
| 190 | } |
| 191 | |
| 192 | static int yop_read_seek(AVFormatContext *s, int stream_index, |
| 193 | int64_t timestamp, int flags) |
| 194 | { |
| 195 | YopDecContext *yop = s->priv_data; |
| 196 | int64_t frame_pos, pos_min, pos_max; |
| 197 | int frame_count; |
| 198 | |
| 199 | if (!stream_index) |
| 200 | return -1; |
| 201 | |
| 202 | pos_min = s->data_offset; |
| 203 | pos_max = avio_size(s->pb) - yop->frame_size; |
| 204 | frame_count = (pos_max - pos_min) / yop->frame_size; |
| 205 | |
| 206 | timestamp = FFMAX(0, FFMIN(frame_count, timestamp)); |
| 207 | |
| 208 | frame_pos = timestamp * yop->frame_size + pos_min; |
| 209 | |
| 210 | if (avio_seek(s->pb, frame_pos, SEEK_SET) < 0) |
| 211 | return -1; |
| 212 | |
| 213 | av_free_packet(&yop->video_packet); |
| 214 | yop->odd_frame = timestamp & 1; |
| 215 | |
| 216 | return 0; |
| 217 | } |
| 218 | |
| 219 | AVInputFormat ff_yop_demuxer = { |
| 220 | .name = "yop", |
| 221 | .long_name = NULL_IF_CONFIG_SMALL("Psygnosis YOP"), |
| 222 | .priv_data_size = sizeof(YopDecContext), |
| 223 | .read_probe = yop_probe, |
| 224 | .read_header = yop_read_header, |
| 225 | .read_packet = yop_read_packet, |
| 226 | .read_close = yop_read_close, |
| 227 | .read_seek = yop_read_seek, |
| 228 | .extensions = "yop", |
| 229 | .flags = AVFMT_GENERIC_INDEX, |
| 230 | }; |