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n3.4.14
libavformat/idcin.c
380 строк
13 KB
Clément Bœsch
Merge commit '41ed7ab45fc693f7d7fc35664c0233f4c32d69bb'
21 июн 2016, 22:55
21 июн 2016, 22:55
8ef57a0
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/* * 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. * Probabilistically, 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->codecpar->codec_type = AVMEDIA_TYPE_VIDEO; st->codecpar->codec_id = AV_CODEC_ID_IDCIN; st->codecpar->codec_tag = 0; /* no fourcc */ st->codecpar->width = width; st->codecpar->height = height; /* load up the Huffman tables into extradata */ if ((ret = ff_get_extradata(s, st->codecpar, 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->codecpar->codec_type = AVMEDIA_TYPE_AUDIO; st->codecpar->codec_tag = 1; st->codecpar->channels = channels; st->codecpar->channel_layout = channels > 1 ? AV_CH_LAYOUT_STEREO : AV_CH_LAYOUT_MONO; st->codecpar->sample_rate = sample_rate; st->codecpar->bits_per_coded_sample = bytes_per_sample * 8; st->codecpar->bit_rate = sample_rate * bytes_per_sample * 8 * channels; st->codecpar->block_align = idcin->block_align = bytes_per_sample * channels; if (bytes_per_sample == 1) st->codecpar->codec_id = AV_CODEC_ID_PCM_U8; else st->codecpar->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, };