| /* |
| * Westwood Studios Multimedia Formats Demuxer (VQA, AUD) |
| * 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 libavformat/westwood.c |
| * Westwood Studios VQA & AUD file demuxers |
| * by Mike Melanson (melanson@pcisys.net) |
| * for more information on the Westwood file formats, visit: |
| * http://www.pcisys.net/~melanson/codecs/ |
| * http://www.geocities.com/SiliconValley/8682/aud3.txt |
| * |
| * Implementation note: There is no definite file signature for AUD files. |
| * The demuxer uses a probabilistic strategy for content detection. This |
| * entails performing sanity checks on certain header values in order to |
| * qualify a file. Refer to wsaud_probe() for the precise parameters. |
| */ |
| |
| #include "libavutil/intreadwrite.h" |
| #include "avformat.h" |
| |
| #define AUD_HEADER_SIZE 12 |
| #define AUD_CHUNK_PREAMBLE_SIZE 8 |
| #define AUD_CHUNK_SIGNATURE 0x0000DEAF |
| |
| #define FORM_TAG MKBETAG('F', 'O', 'R', 'M') |
| #define WVQA_TAG MKBETAG('W', 'V', 'Q', 'A') |
| #define VQHD_TAG MKBETAG('V', 'Q', 'H', 'D') |
| #define FINF_TAG MKBETAG('F', 'I', 'N', 'F') |
| #define SND0_TAG MKBETAG('S', 'N', 'D', '0') |
| #define SND1_TAG MKBETAG('S', 'N', 'D', '1') |
| #define SND2_TAG MKBETAG('S', 'N', 'D', '2') |
| #define VQFR_TAG MKBETAG('V', 'Q', 'F', 'R') |
| |
| /* don't know what these tags are for, but acknowledge their existence */ |
| #define CINF_TAG MKBETAG('C', 'I', 'N', 'F') |
| #define CINH_TAG MKBETAG('C', 'I', 'N', 'H') |
| #define CIND_TAG MKBETAG('C', 'I', 'N', 'D') |
| #define PINF_TAG MKBETAG('P', 'I', 'N', 'F') |
| #define PINH_TAG MKBETAG('P', 'I', 'N', 'H') |
| #define PIND_TAG MKBETAG('P', 'I', 'N', 'D') |
| #define CMDS_TAG MKBETAG('C', 'M', 'D', 'S') |
| |
| #define VQA_HEADER_SIZE 0x2A |
| #define VQA_FRAMERATE 15 |
| #define VQA_VIDEO_PTS_INC (90000 / VQA_FRAMERATE) |
| #define VQA_PREAMBLE_SIZE 8 |
| |
| typedef struct WsAudDemuxContext { |
| int audio_samplerate; |
| int audio_channels; |
| int audio_bits; |
| enum CodecID audio_type; |
| int audio_stream_index; |
| int64_t audio_frame_counter; |
| } WsAudDemuxContext; |
| |
| typedef struct WsVqaDemuxContext { |
| int audio_samplerate; |
| int audio_channels; |
| int audio_bits; |
| |
| int audio_stream_index; |
| int video_stream_index; |
| |
| int64_t audio_frame_counter; |
| int64_t video_pts; |
| } WsVqaDemuxContext; |
| |
| static int wsaud_probe(AVProbeData *p) |
| { |
| int field; |
| |
| /* Probabilistic content detection strategy: There is no file signature |
| * so perform sanity checks on various header parameters: |
| * 8000 <= sample rate (16 bits) <= 48000 ==> 40001 acceptable numbers |
| * flags <= 0x03 (2 LSBs are used) ==> 4 acceptable numbers |
| * compression type (8 bits) = 1 or 99 ==> 2 acceptable numbers |
| * first audio chunk signature (32 bits) ==> 1 acceptable number |
| * The number space contains 2^64 numbers. There are 40001 * 4 * 2 * 1 = |
| * 320008 acceptable number combinations. |
| */ |
| |
| if (p->buf_size < AUD_HEADER_SIZE + AUD_CHUNK_PREAMBLE_SIZE) |
| return 0; |
| |
| /* check sample rate */ |
| field = AV_RL16(&p->buf[0]); |
| if ((field < 8000) || (field > 48000)) |
| return 0; |
| |
| /* enforce the rule that the top 6 bits of this flags field are reserved (0); |
| * this might not be true, but enforce it until deemed unnecessary */ |
| if (p->buf[10] & 0xFC) |
| return 0; |
| |
| /* note: only check for WS IMA (type 99) right now since there is no |
| * support for type 1 */ |
| if (p->buf[11] != 99) |
| return 0; |
| |
| /* read ahead to the first audio chunk and validate the first header signature */ |
| if (AV_RL32(&p->buf[16]) != AUD_CHUNK_SIGNATURE) |
| return 0; |
| |
| /* return 1/2 certainty since this file check is a little sketchy */ |
| return AVPROBE_SCORE_MAX / 2; |
| } |
| |
| static int wsaud_read_header(AVFormatContext *s, |
| AVFormatParameters *ap) |
| { |
| WsAudDemuxContext *wsaud = s->priv_data; |
| ByteIOContext *pb = s->pb; |
| AVStream *st; |
| unsigned char header[AUD_HEADER_SIZE]; |
| |
| if (get_buffer(pb, header, AUD_HEADER_SIZE) != AUD_HEADER_SIZE) |
| return AVERROR(EIO); |
| wsaud->audio_samplerate = AV_RL16(&header[0]); |
| if (header[11] == 99) |
| wsaud->audio_type = CODEC_ID_ADPCM_IMA_WS; |
| else |
| return AVERROR_INVALIDDATA; |
| |
| /* flag 0 indicates stereo */ |
| wsaud->audio_channels = (header[10] & 0x1) + 1; |
| /* flag 1 indicates 16 bit audio */ |
| wsaud->audio_bits = (((header[10] & 0x2) >> 1) + 1) * 8; |
| |
| /* initialize the audio decoder stream */ |
| st = av_new_stream(s, 0); |
| if (!st) |
| return AVERROR(ENOMEM); |
| av_set_pts_info(st, 33, 1, wsaud->audio_samplerate); |
| st->codec->codec_type = CODEC_TYPE_AUDIO; |
| st->codec->codec_id = wsaud->audio_type; |
| st->codec->codec_tag = 0; /* no tag */ |
| st->codec->channels = wsaud->audio_channels; |
| st->codec->sample_rate = wsaud->audio_samplerate; |
| st->codec->bits_per_coded_sample = wsaud->audio_bits; |
| st->codec->bit_rate = st->codec->channels * st->codec->sample_rate * |
| st->codec->bits_per_coded_sample / 4; |
| st->codec->block_align = st->codec->channels * st->codec->bits_per_coded_sample; |
| |
| wsaud->audio_stream_index = st->index; |
| wsaud->audio_frame_counter = 0; |
| |
| return 0; |
| } |
| |
| static int wsaud_read_packet(AVFormatContext *s, |
| AVPacket *pkt) |
| { |
| WsAudDemuxContext *wsaud = s->priv_data; |
| ByteIOContext *pb = s->pb; |
| unsigned char preamble[AUD_CHUNK_PREAMBLE_SIZE]; |
| unsigned int chunk_size; |
| int ret = 0; |
| |
| if (get_buffer(pb, preamble, AUD_CHUNK_PREAMBLE_SIZE) != |
| AUD_CHUNK_PREAMBLE_SIZE) |
| return AVERROR(EIO); |
| |
| /* validate the chunk */ |
| if (AV_RL32(&preamble[4]) != AUD_CHUNK_SIGNATURE) |
| return AVERROR_INVALIDDATA; |
| |
| chunk_size = AV_RL16(&preamble[0]); |
| ret= av_get_packet(pb, pkt, chunk_size); |
| if (ret != chunk_size) |
| return AVERROR(EIO); |
| pkt->stream_index = wsaud->audio_stream_index; |
| pkt->pts = wsaud->audio_frame_counter; |
| pkt->pts /= wsaud->audio_samplerate; |
| |
| /* 2 samples/byte, 1 or 2 samples per frame depending on stereo */ |
| wsaud->audio_frame_counter += (chunk_size * 2) / wsaud->audio_channels; |
| |
| return ret; |
| } |
| |
| static int wsvqa_probe(AVProbeData *p) |
| { |
| /* need 12 bytes to qualify */ |
| if (p->buf_size < 12) |
| return 0; |
| |
| /* check for the VQA signatures */ |
| if ((AV_RB32(&p->buf[0]) != FORM_TAG) || |
| (AV_RB32(&p->buf[8]) != WVQA_TAG)) |
| return 0; |
| |
| return AVPROBE_SCORE_MAX; |
| } |
| |
| static int wsvqa_read_header(AVFormatContext *s, |
| AVFormatParameters *ap) |
| { |
| WsVqaDemuxContext *wsvqa = s->priv_data; |
| ByteIOContext *pb = s->pb; |
| AVStream *st; |
| unsigned char *header; |
| unsigned char scratch[VQA_PREAMBLE_SIZE]; |
| unsigned int chunk_tag; |
| unsigned int chunk_size; |
| |
| /* initialize the video decoder stream */ |
| st = av_new_stream(s, 0); |
| if (!st) |
| return AVERROR(ENOMEM); |
| av_set_pts_info(st, 33, 1, VQA_FRAMERATE); |
| wsvqa->video_stream_index = st->index; |
| st->codec->codec_type = CODEC_TYPE_VIDEO; |
| st->codec->codec_id = CODEC_ID_WS_VQA; |
| st->codec->codec_tag = 0; /* no fourcc */ |
| |
| /* skip to the start of the VQA header */ |
| url_fseek(pb, 20, SEEK_SET); |
| |
| /* the VQA header needs to go to the decoder */ |
| st->codec->extradata_size = VQA_HEADER_SIZE; |
| st->codec->extradata = av_mallocz(VQA_HEADER_SIZE + FF_INPUT_BUFFER_PADDING_SIZE); |
| header = (unsigned char *)st->codec->extradata; |
| if (get_buffer(pb, st->codec->extradata, VQA_HEADER_SIZE) != |
| VQA_HEADER_SIZE) { |
| av_free(st->codec->extradata); |
| return AVERROR(EIO); |
| } |
| st->codec->width = AV_RL16(&header[6]); |
| st->codec->height = AV_RL16(&header[8]); |
| |
| /* initialize the audio decoder stream for VQA v1 or nonzero samplerate */ |
| if (AV_RL16(&header[24]) || (AV_RL16(&header[0]) == 1 && AV_RL16(&header[2]) == 1)) { |
| st = av_new_stream(s, 0); |
| if (!st) |
| return AVERROR(ENOMEM); |
| av_set_pts_info(st, 33, 1, VQA_FRAMERATE); |
| st->codec->codec_type = CODEC_TYPE_AUDIO; |
| if (AV_RL16(&header[0]) == 1) |
| st->codec->codec_id = CODEC_ID_WESTWOOD_SND1; |
| else |
| st->codec->codec_id = CODEC_ID_ADPCM_IMA_WS; |
| st->codec->codec_tag = 0; /* no tag */ |
| st->codec->sample_rate = AV_RL16(&header[24]); |
| if (!st->codec->sample_rate) |
| st->codec->sample_rate = 22050; |
| st->codec->channels = header[26]; |
| if (!st->codec->channels) |
| st->codec->channels = 1; |
| st->codec->bits_per_coded_sample = 16; |
| st->codec->bit_rate = st->codec->channels * st->codec->sample_rate * |
| st->codec->bits_per_coded_sample / 4; |
| st->codec->block_align = st->codec->channels * st->codec->bits_per_coded_sample; |
| |
| wsvqa->audio_stream_index = st->index; |
| wsvqa->audio_samplerate = st->codec->sample_rate; |
| wsvqa->audio_channels = st->codec->channels; |
| wsvqa->audio_frame_counter = 0; |
| } |
| |
| /* there are 0 or more chunks before the FINF chunk; iterate until |
| * FINF has been skipped and the file will be ready to be demuxed */ |
| do { |
| if (get_buffer(pb, scratch, VQA_PREAMBLE_SIZE) != VQA_PREAMBLE_SIZE) { |
| av_free(st->codec->extradata); |
| return AVERROR(EIO); |
| } |
| chunk_tag = AV_RB32(&scratch[0]); |
| chunk_size = AV_RB32(&scratch[4]); |
| |
| /* catch any unknown header tags, for curiousity */ |
| switch (chunk_tag) { |
| case CINF_TAG: |
| case CINH_TAG: |
| case CIND_TAG: |
| case PINF_TAG: |
| case PINH_TAG: |
| case PIND_TAG: |
| case FINF_TAG: |
| case CMDS_TAG: |
| break; |
| |
| default: |
| av_log (s, AV_LOG_ERROR, " note: unknown chunk seen (%c%c%c%c)\n", |
| scratch[0], scratch[1], |
| scratch[2], scratch[3]); |
| break; |
| } |
| |
| url_fseek(pb, chunk_size, SEEK_CUR); |
| } while (chunk_tag != FINF_TAG); |
| |
| wsvqa->video_pts = wsvqa->audio_frame_counter = 0; |
| |
| return 0; |
| } |
| |
| static int wsvqa_read_packet(AVFormatContext *s, |
| AVPacket *pkt) |
| { |
| WsVqaDemuxContext *wsvqa = s->priv_data; |
| ByteIOContext *pb = s->pb; |
| int ret = -1; |
| unsigned char preamble[VQA_PREAMBLE_SIZE]; |
| unsigned int chunk_type; |
| unsigned int chunk_size; |
| int skip_byte; |
| |
| while (get_buffer(pb, preamble, VQA_PREAMBLE_SIZE) == VQA_PREAMBLE_SIZE) { |
| chunk_type = AV_RB32(&preamble[0]); |
| chunk_size = AV_RB32(&preamble[4]); |
| skip_byte = chunk_size & 0x01; |
| |
| if ((chunk_type == SND1_TAG) || (chunk_type == SND2_TAG) || (chunk_type == VQFR_TAG)) { |
| |
| if (av_new_packet(pkt, chunk_size)) |
| return AVERROR(EIO); |
| ret = get_buffer(pb, pkt->data, chunk_size); |
| if (ret != chunk_size) { |
| av_free_packet(pkt); |
| return AVERROR(EIO); |
| } |
| |
| if (chunk_type == SND2_TAG) { |
| pkt->stream_index = wsvqa->audio_stream_index; |
| /* 2 samples/byte, 1 or 2 samples per frame depending on stereo */ |
| wsvqa->audio_frame_counter += (chunk_size * 2) / wsvqa->audio_channels; |
| } else if(chunk_type == SND1_TAG) { |
| pkt->stream_index = wsvqa->audio_stream_index; |
| /* unpacked size is stored in header */ |
| wsvqa->audio_frame_counter += AV_RL16(pkt->data) / wsvqa->audio_channels; |
| } else { |
| pkt->stream_index = wsvqa->video_stream_index; |
| wsvqa->video_pts += VQA_VIDEO_PTS_INC; |
| } |
| /* stay on 16-bit alignment */ |
| if (skip_byte) |
| url_fseek(pb, 1, SEEK_CUR); |
| |
| return ret; |
| } else { |
| switch(chunk_type){ |
| case CMDS_TAG: |
| case SND0_TAG: |
| break; |
| default: |
| av_log(s, AV_LOG_INFO, "Skipping unknown chunk 0x%08X\n", chunk_type); |
| } |
| url_fseek(pb, chunk_size + skip_byte, SEEK_CUR); |
| } |
| } |
| |
| return ret; |
| } |
| |
| #if CONFIG_WSAUD_DEMUXER |
| AVInputFormat wsaud_demuxer = { |
| "wsaud", |
| NULL_IF_CONFIG_SMALL("Westwood Studios audio format"), |
| sizeof(WsAudDemuxContext), |
| wsaud_probe, |
| wsaud_read_header, |
| wsaud_read_packet, |
| }; |
| #endif |
| #if CONFIG_WSVQA_DEMUXER |
| AVInputFormat wsvqa_demuxer = { |
| "wsvqa", |
| NULL_IF_CONFIG_SMALL("Westwood Studios VQA format"), |
| sizeof(WsVqaDemuxContext), |
| wsvqa_probe, |
| wsvqa_read_header, |
| wsvqa_read_packet, |
| }; |
| #endif |