| /* |
| * id Quake II CIN File Demuxer |
| * 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 |
| * id Quake II CIN file demuxer by Mike Melanson (melanson@pcisys.net) |
| * For more information about the id CIN format, visit: |
| * http://www.csse.monash.edu.au/~timf/ |
| * |
| * CIN is a somewhat quirky and ill-defined format. Here are some notes |
| * for anyone trying to understand the technical details of this format: |
| * |
| * The format has no definite file signature. This is problematic for a |
| * general-purpose media player that wants to automatically detect file |
| * types. However, a CIN file does start with 5 32-bit numbers that |
| * specify audio and video parameters. This demuxer gets around the lack |
| * of file signature by performing sanity checks on those parameters. |
| * Probabalistically, this is a reasonable solution since the number of |
| * valid combinations of the 5 parameters is a very small subset of the |
| * total 160-bit number space. |
| * |
| * Refer to the function idcin_probe() for the precise A/V parameters |
| * that this demuxer allows. |
| * |
| * Next, each audio and video frame has a duration of 1/14 sec. If the |
| * audio sample rate is a multiple of the common frequency 22050 Hz it will |
| * divide evenly by 14. However, if the sample rate is 11025 Hz: |
| * 11025 (samples/sec) / 14 (frames/sec) = 787.5 (samples/frame) |
| * The way the CIN stores audio in this case is by storing 787 sample |
| * frames in the first audio frame and 788 sample frames in the second |
| * audio frame. Therefore, the total number of bytes in an audio frame |
| * is given as: |
| * audio frame #0: 787 * (bytes/sample) * (# channels) bytes in frame |
| * audio frame #1: 788 * (bytes/sample) * (# channels) bytes in frame |
| * audio frame #2: 787 * (bytes/sample) * (# channels) bytes in frame |
| * audio frame #3: 788 * (bytes/sample) * (# channels) bytes in frame |
| * |
| * Finally, not all id CIN creation tools agree on the resolution of the |
| * color palette, apparently. Some creation tools specify red, green, and |
| * blue palette components in terms of 6-bit VGA color DAC values which |
| * range from 0..63. Other tools specify the RGB components as full 8-bit |
| * values that range from 0..255. Since there are no markers in the file to |
| * differentiate between the two variants, this demuxer uses the following |
| * heuristic: |
| * - load the 768 palette bytes from disk |
| * - assume that they will need to be shifted left by 2 bits to |
| * transform them from 6-bit values to 8-bit values |
| * - scan through all 768 palette bytes |
| * - if any bytes exceed 63, do not shift the bytes at all before |
| * transmitting them to the video decoder |
| */ |
| |
| #include "libavutil/channel_layout.h" |
| #include "libavutil/imgutils.h" |
| #include "libavutil/intreadwrite.h" |
| #include "avformat.h" |
| #include "internal.h" |
| |
| #define HUFFMAN_TABLE_SIZE (64 * 1024) |
| #define IDCIN_FPS 14 |
| |
| typedef struct IdcinDemuxContext { |
| int video_stream_index; |
| int audio_stream_index; |
| int audio_chunk_size1; |
| int audio_chunk_size2; |
| int block_align; |
| |
| /* demux state variables */ |
| int current_audio_chunk; |
| int next_chunk_is_video; |
| int audio_present; |
| int64_t first_pkt_pos; |
| } IdcinDemuxContext; |
| |
| static int idcin_probe(AVProbeData *p) |
| { |
| unsigned int number, sample_rate; |
| unsigned int w, h; |
| int i; |
| |
| /* |
| * This is what you could call a "probabilistic" file check: id CIN |
| * files don't have a definite file signature. In lieu of such a marker, |
| * perform sanity checks on the 5 32-bit header fields: |
| * width, height: greater than 0, less than or equal to 1024 |
| * audio sample rate: greater than or equal to 8000, less than or |
| * equal to 48000, or 0 for no audio |
| * audio sample width (bytes/sample): 0 for no audio, or 1 or 2 |
| * audio channels: 0 for no audio, or 1 or 2 |
| */ |
| |
| /* check we have enough data to do all checks, otherwise the |
| 0-padding may cause a wrong recognition */ |
| if (p->buf_size < 20 + HUFFMAN_TABLE_SIZE + 12) |
| return 0; |
| |
| /* check the video width */ |
| w = AV_RL32(&p->buf[0]); |
| if ((w == 0) || (w > 1024)) |
| return 0; |
| |
| /* check the video height */ |
| h = AV_RL32(&p->buf[4]); |
| if ((h == 0) || (h > 1024)) |
| return 0; |
| |
| /* check the audio sample rate */ |
| sample_rate = AV_RL32(&p->buf[8]); |
| if (sample_rate && (sample_rate < 8000 || sample_rate > 48000)) |
| return 0; |
| |
| /* check the audio bytes/sample */ |
| number = AV_RL32(&p->buf[12]); |
| if (number > 2 || sample_rate && !number) |
| return 0; |
| |
| /* check the audio channels */ |
| number = AV_RL32(&p->buf[16]); |
| if (number > 2 || sample_rate && !number) |
| return 0; |
| |
| i = 20 + HUFFMAN_TABLE_SIZE; |
| if (AV_RL32(&p->buf[i]) == 1) |
| i += 768; |
| |
| if (i+12 > p->buf_size || AV_RL32(&p->buf[i+8]) != w*h) |
| return 1; |
| |
| /* return half certainty since this check is a bit sketchy */ |
| return AVPROBE_SCORE_EXTENSION; |
| } |
| |
| static int idcin_read_header(AVFormatContext *s) |
| { |
| AVIOContext *pb = s->pb; |
| IdcinDemuxContext *idcin = s->priv_data; |
| AVStream *st; |
| unsigned int width, height; |
| unsigned int sample_rate, bytes_per_sample, channels; |
| int ret; |
| |
| /* get the 5 header parameters */ |
| width = avio_rl32(pb); |
| height = avio_rl32(pb); |
| sample_rate = avio_rl32(pb); |
| bytes_per_sample = avio_rl32(pb); |
| channels = avio_rl32(pb); |
| |
| if (s->pb->eof_reached) { |
| av_log(s, AV_LOG_ERROR, "incomplete header\n"); |
| return s->pb->error ? s->pb->error : AVERROR_EOF; |
| } |
| |
| if (av_image_check_size(width, height, 0, s) < 0) |
| return AVERROR_INVALIDDATA; |
| if (sample_rate > 0) { |
| if (sample_rate < 14 || sample_rate > INT_MAX) { |
| av_log(s, AV_LOG_ERROR, "invalid sample rate: %u\n", sample_rate); |
| return AVERROR_INVALIDDATA; |
| } |
| if (bytes_per_sample < 1 || bytes_per_sample > 2) { |
| av_log(s, AV_LOG_ERROR, "invalid bytes per sample: %u\n", |
| bytes_per_sample); |
| return AVERROR_INVALIDDATA; |
| } |
| if (channels < 1 || channels > 2) { |
| av_log(s, AV_LOG_ERROR, "invalid channels: %u\n", channels); |
| return AVERROR_INVALIDDATA; |
| } |
| idcin->audio_present = 1; |
| } else { |
| /* if sample rate is 0, assume no audio */ |
| idcin->audio_present = 0; |
| } |
| |
| st = avformat_new_stream(s, NULL); |
| if (!st) |
| return AVERROR(ENOMEM); |
| avpriv_set_pts_info(st, 33, 1, IDCIN_FPS); |
| st->start_time = 0; |
| idcin->video_stream_index = st->index; |
| st->codec->codec_type = AVMEDIA_TYPE_VIDEO; |
| st->codec->codec_id = AV_CODEC_ID_IDCIN; |
| st->codec->codec_tag = 0; /* no fourcc */ |
| st->codec->width = width; |
| st->codec->height = height; |
| |
| /* load up the Huffman tables into extradata */ |
| if ((ret = ff_get_extradata(st->codec, pb, HUFFMAN_TABLE_SIZE)) < 0) |
| return ret; |
| |
| if (idcin->audio_present) { |
| idcin->audio_present = 1; |
| st = avformat_new_stream(s, NULL); |
| if (!st) |
| return AVERROR(ENOMEM); |
| avpriv_set_pts_info(st, 63, 1, sample_rate); |
| st->start_time = 0; |
| idcin->audio_stream_index = st->index; |
| st->codec->codec_type = AVMEDIA_TYPE_AUDIO; |
| st->codec->codec_tag = 1; |
| st->codec->channels = channels; |
| st->codec->channel_layout = channels > 1 ? AV_CH_LAYOUT_STEREO : |
| AV_CH_LAYOUT_MONO; |
| st->codec->sample_rate = sample_rate; |
| st->codec->bits_per_coded_sample = bytes_per_sample * 8; |
| st->codec->bit_rate = sample_rate * bytes_per_sample * 8 * channels; |
| st->codec->block_align = idcin->block_align = bytes_per_sample * channels; |
| if (bytes_per_sample == 1) |
| st->codec->codec_id = AV_CODEC_ID_PCM_U8; |
| else |
| st->codec->codec_id = AV_CODEC_ID_PCM_S16LE; |
| |
| if (sample_rate % 14 != 0) { |
| idcin->audio_chunk_size1 = (sample_rate / 14) * |
| bytes_per_sample * channels; |
| idcin->audio_chunk_size2 = (sample_rate / 14 + 1) * |
| bytes_per_sample * channels; |
| } else { |
| idcin->audio_chunk_size1 = idcin->audio_chunk_size2 = |
| (sample_rate / 14) * bytes_per_sample * channels; |
| } |
| idcin->current_audio_chunk = 0; |
| } |
| |
| idcin->next_chunk_is_video = 1; |
| idcin->first_pkt_pos = avio_tell(s->pb); |
| |
| return 0; |
| } |
| |
| static int idcin_read_packet(AVFormatContext *s, |
| AVPacket *pkt) |
| { |
| int ret; |
| unsigned int command; |
| unsigned int chunk_size; |
| IdcinDemuxContext *idcin = s->priv_data; |
| AVIOContext *pb = s->pb; |
| int i; |
| int palette_scale; |
| unsigned char r, g, b; |
| unsigned char palette_buffer[768]; |
| uint32_t palette[256]; |
| |
| if (avio_feof(s->pb)) |
| return s->pb->error ? s->pb->error : AVERROR_EOF; |
| |
| if (idcin->next_chunk_is_video) { |
| command = avio_rl32(pb); |
| if (command == 2) { |
| return AVERROR(EIO); |
| } else if (command == 1) { |
| /* trigger a palette change */ |
| ret = avio_read(pb, palette_buffer, 768); |
| if (ret < 0) { |
| return ret; |
| } else if (ret != 768) { |
| av_log(s, AV_LOG_ERROR, "incomplete packet\n"); |
| return AVERROR(EIO); |
| } |
| /* scale the palette as necessary */ |
| palette_scale = 2; |
| for (i = 0; i < 768; i++) |
| if (palette_buffer[i] > 63) { |
| palette_scale = 0; |
| break; |
| } |
| |
| for (i = 0; i < 256; i++) { |
| r = palette_buffer[i * 3 ] << palette_scale; |
| g = palette_buffer[i * 3 + 1] << palette_scale; |
| b = palette_buffer[i * 3 + 2] << palette_scale; |
| palette[i] = (0xFFU << 24) | (r << 16) | (g << 8) | (b); |
| if (palette_scale == 2) |
| palette[i] |= palette[i] >> 6 & 0x30303; |
| } |
| } |
| |
| if (s->pb->eof_reached) { |
| av_log(s, AV_LOG_ERROR, "incomplete packet\n"); |
| return s->pb->error ? s->pb->error : AVERROR_EOF; |
| } |
| chunk_size = avio_rl32(pb); |
| if (chunk_size < 4 || chunk_size > INT_MAX - 4) { |
| av_log(s, AV_LOG_ERROR, "invalid chunk size: %u\n", chunk_size); |
| return AVERROR_INVALIDDATA; |
| } |
| /* skip the number of decoded bytes (always equal to width * height) */ |
| avio_skip(pb, 4); |
| chunk_size -= 4; |
| ret= av_get_packet(pb, pkt, chunk_size); |
| if (ret < 0) |
| return ret; |
| else if (ret != chunk_size) { |
| av_log(s, AV_LOG_ERROR, "incomplete packet\n"); |
| av_packet_unref(pkt); |
| return AVERROR(EIO); |
| } |
| if (command == 1) { |
| uint8_t *pal; |
| |
| pal = av_packet_new_side_data(pkt, AV_PKT_DATA_PALETTE, |
| AVPALETTE_SIZE); |
| if (!pal) { |
| av_packet_unref(pkt); |
| return AVERROR(ENOMEM); |
| } |
| memcpy(pal, palette, AVPALETTE_SIZE); |
| pkt->flags |= AV_PKT_FLAG_KEY; |
| } |
| pkt->stream_index = idcin->video_stream_index; |
| pkt->duration = 1; |
| } else { |
| /* send out the audio chunk */ |
| if (idcin->current_audio_chunk) |
| chunk_size = idcin->audio_chunk_size2; |
| else |
| chunk_size = idcin->audio_chunk_size1; |
| ret= av_get_packet(pb, pkt, chunk_size); |
| if (ret < 0) |
| return ret; |
| pkt->stream_index = idcin->audio_stream_index; |
| pkt->duration = chunk_size / idcin->block_align; |
| |
| idcin->current_audio_chunk ^= 1; |
| } |
| |
| if (idcin->audio_present) |
| idcin->next_chunk_is_video ^= 1; |
| |
| return 0; |
| } |
| |
| static int idcin_read_seek(AVFormatContext *s, int stream_index, |
| int64_t timestamp, int flags) |
| { |
| IdcinDemuxContext *idcin = s->priv_data; |
| |
| if (idcin->first_pkt_pos > 0) { |
| int64_t ret = avio_seek(s->pb, idcin->first_pkt_pos, SEEK_SET); |
| if (ret < 0) |
| return ret; |
| ff_update_cur_dts(s, s->streams[idcin->video_stream_index], 0); |
| idcin->next_chunk_is_video = 1; |
| idcin->current_audio_chunk = 0; |
| return 0; |
| } |
| return -1; |
| } |
| |
| AVInputFormat ff_idcin_demuxer = { |
| .name = "idcin", |
| .long_name = NULL_IF_CONFIG_SMALL("id Cinematic"), |
| .priv_data_size = sizeof(IdcinDemuxContext), |
| .read_probe = idcin_probe, |
| .read_header = idcin_read_header, |
| .read_packet = idcin_read_packet, |
| .read_seek = idcin_read_seek, |
| .flags = AVFMT_NO_BYTE_SEEK, |
| }; |
