libavformat/westwood_vqa.c - third_party/ffmpeg - Git at Google

 /*
  * Westwood Studios VQA Format 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
  * Westwood Studios VQA file demuxer
  * 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
  */

 #include "libavutil/intreadwrite.h"
 #include "avformat.h"
 #include "internal.h"

 #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_PREAMBLE_SIZE 8

 typedef struct WsVqaDemuxContext {
     int audio_channels;
     int audio_stream_index;
     int video_stream_index;
 } WsVqaDemuxContext;

 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;
     AVIOContext *pb = s->pb;
     AVStream *st;
     unsigned char *header;
     unsigned char scratch[VQA_PREAMBLE_SIZE];
     unsigned int chunk_tag;
     unsigned int chunk_size;
     int fps, version, flags, sample_rate, channels;

     /* initialize the video decoder stream */
     st = avformat_new_stream(s, NULL);
     if (!st)
         return AVERROR(ENOMEM);
     st->start_time = 0;
     wsvqa->video_stream_index = st->index;
     st->codec->codec_type = AVMEDIA_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 */
     avio_seek(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 (avio_read(pb, st->codec->extradata, VQA_HEADER_SIZE) !=
         VQA_HEADER_SIZE) {
         return AVERROR(EIO);
     }
     st->codec->width = AV_RL16(&header[6]);
     st->codec->height = AV_RL16(&header[8]);
     fps = header[12];
     if (fps < 1 || fps > 30) {
         av_log(s, AV_LOG_ERROR, "invalid fps: %d\n", fps);
         return AVERROR_INVALIDDATA;
     }
     avpriv_set_pts_info(st, 64, 1, fps);

     /* initialize the audio decoder stream for VQA v1 or nonzero samplerate */
     version     = AV_RL16(&header[ 0]);
     flags       = AV_RL16(&header[ 2]);
     sample_rate = AV_RL16(&header[24]);
     channels    =          header[26];
     if (sample_rate || (version == 1 && flags == 1)) {
         st = avformat_new_stream(s, NULL);
         if (!st)
             return AVERROR(ENOMEM);
         st->start_time = 0;
         st->codec->codec_type = AVMEDIA_TYPE_AUDIO;

         st->codec->extradata_size = VQA_HEADER_SIZE;
         st->codec->extradata = av_mallocz(VQA_HEADER_SIZE + FF_INPUT_BUFFER_PADDING_SIZE);
         if (!st->codec->extradata)
             return AVERROR(ENOMEM);
         memcpy(st->codec->extradata, header, VQA_HEADER_SIZE);

         if (!sample_rate)
             sample_rate = 22050;
         st->codec->sample_rate = sample_rate;
         avpriv_set_pts_info(st, 64, 1, st->codec->sample_rate);

         if (!channels)
             channels = 1;
         st->codec->channels = channels;

         switch (version) {
         case 1:
             st->codec->codec_id = CODEC_ID_WESTWOOD_SND1;
             break;
         case 2:
         case 3:
             st->codec->codec_id = CODEC_ID_ADPCM_IMA_WS;
             st->codec->bits_per_coded_sample = 4;
             st->codec->bit_rate = channels * sample_rate * 4;
             break;
         default:
             /* NOTE: version 0 is supposedly raw pcm_u8 or pcm_s16le, but we do
                      not have any samples to validate this */
             av_log_ask_for_sample(s, "VQA version %d audio\n", version);
             return AVERROR_PATCHWELCOME;
         }

         wsvqa->audio_stream_index = st->index;
         wsvqa->audio_channels = st->codec->channels;
     }

     /* 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 (avio_read(pb, scratch, VQA_PREAMBLE_SIZE) != VQA_PREAMBLE_SIZE)
             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;
         }

         avio_skip(pb, chunk_size);
     } while (chunk_tag != FINF_TAG);

     return 0;
 }

 static int wsvqa_read_packet(AVFormatContext *s,
                              AVPacket *pkt)
 {
     WsVqaDemuxContext *wsvqa = s->priv_data;
     AVIOContext *pb = s->pb;
     int ret = -1;
     unsigned char preamble[VQA_PREAMBLE_SIZE];
     unsigned int chunk_type;
     unsigned int chunk_size;
     int skip_byte;

     while (avio_read(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 == SND2_TAG || chunk_type == SND1_TAG) && wsvqa->audio_channels == 0) {
             av_log(s, AV_LOG_ERROR, "audio chunk without any audio header information found\n");
             return AVERROR_INVALIDDATA;
         }

         if ((chunk_type == SND1_TAG) || (chunk_type == SND2_TAG) || (chunk_type == VQFR_TAG)) {

             ret= av_get_packet(pb, pkt, chunk_size);
             if (ret<0)
                 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 */
                 pkt->duration = (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 */
                 pkt->duration = AV_RL16(pkt->data) / wsvqa->audio_channels;
             } else {
                 pkt->stream_index = wsvqa->video_stream_index;
                 pkt->duration = 1;
             }
             /* stay on 16-bit alignment */
             if (skip_byte)
                 avio_skip(pb, 1);

             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);
             }
             avio_skip(pb, chunk_size + skip_byte);
         }
     }

     return ret;
 }

 AVInputFormat ff_wsvqa_demuxer = {
     .name           = "wsvqa",
     .long_name      = NULL_IF_CONFIG_SMALL("Westwood Studios VQA format"),
     .priv_data_size = sizeof(WsVqaDemuxContext),
     .read_probe     = wsvqa_probe,
     .read_header    = wsvqa_read_header,
     .read_packet    = wsvqa_read_packet,
 };
	/*
	* Westwood Studios VQA Format 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
	* Westwood Studios VQA file demuxer
	* 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
	*/

	#include "libavutil/intreadwrite.h"
	#include "avformat.h"
	#include "internal.h"

	#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_PREAMBLE_SIZE 8

	typedef struct WsVqaDemuxContext {
	int audio_channels;
	int audio_stream_index;
	int video_stream_index;
	} WsVqaDemuxContext;

	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;
	AVIOContext *pb = s->pb;
	AVStream *st;
	unsigned char *header;
	unsigned char scratch[VQA_PREAMBLE_SIZE];
	unsigned int chunk_tag;
	unsigned int chunk_size;
	int fps, version, flags, sample_rate, channels;

	/* initialize the video decoder stream */
	st = avformat_new_stream(s, NULL);
	if (!st)
	return AVERROR(ENOMEM);
	st->start_time = 0;
	wsvqa->video_stream_index = st->index;
	st->codec->codec_type = AVMEDIA_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 */
	avio_seek(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 (avio_read(pb, st->codec->extradata, VQA_HEADER_SIZE) !=
	VQA_HEADER_SIZE) {
	return AVERROR(EIO);
	}
	st->codec->width = AV_RL16(&header[6]);
	st->codec->height = AV_RL16(&header[8]);
	fps = header[12];
	if (fps < 1 \|\| fps > 30) {
	av_log(s, AV_LOG_ERROR, "invalid fps: %d\n", fps);
	return AVERROR_INVALIDDATA;
	}
	avpriv_set_pts_info(st, 64, 1, fps);

	/* initialize the audio decoder stream for VQA v1 or nonzero samplerate */
	version = AV_RL16(&header[ 0]);
	flags = AV_RL16(&header[ 2]);
	sample_rate = AV_RL16(&header[24]);
	channels = header[26];
	if (sample_rate \|\| (version == 1 && flags == 1)) {
	st = avformat_new_stream(s, NULL);
	if (!st)
	return AVERROR(ENOMEM);
	st->start_time = 0;
	st->codec->codec_type = AVMEDIA_TYPE_AUDIO;

	st->codec->extradata_size = VQA_HEADER_SIZE;
	st->codec->extradata = av_mallocz(VQA_HEADER_SIZE + FF_INPUT_BUFFER_PADDING_SIZE);
	if (!st->codec->extradata)
	return AVERROR(ENOMEM);
	memcpy(st->codec->extradata, header, VQA_HEADER_SIZE);

	if (!sample_rate)
	sample_rate = 22050;
	st->codec->sample_rate = sample_rate;
	avpriv_set_pts_info(st, 64, 1, st->codec->sample_rate);

	if (!channels)
	channels = 1;
	st->codec->channels = channels;

	switch (version) {
	case 1:
	st->codec->codec_id = CODEC_ID_WESTWOOD_SND1;
	break;
	case 2:
	case 3:
	st->codec->codec_id = CODEC_ID_ADPCM_IMA_WS;
	st->codec->bits_per_coded_sample = 4;
	st->codec->bit_rate = channels * sample_rate * 4;
	break;
	default:
	/* NOTE: version 0 is supposedly raw pcm_u8 or pcm_s16le, but we do
	not have any samples to validate this */
	av_log_ask_for_sample(s, "VQA version %d audio\n", version);
	return AVERROR_PATCHWELCOME;
	}

	wsvqa->audio_stream_index = st->index;
	wsvqa->audio_channels = st->codec->channels;
	}

	/* 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 (avio_read(pb, scratch, VQA_PREAMBLE_SIZE) != VQA_PREAMBLE_SIZE)
	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;
	}

	avio_skip(pb, chunk_size);
	} while (chunk_tag != FINF_TAG);

	return 0;
	}

	static int wsvqa_read_packet(AVFormatContext *s,
	AVPacket *pkt)
	{
	WsVqaDemuxContext *wsvqa = s->priv_data;
	AVIOContext *pb = s->pb;
	int ret = -1;
	unsigned char preamble[VQA_PREAMBLE_SIZE];
	unsigned int chunk_type;
	unsigned int chunk_size;
	int skip_byte;

	while (avio_read(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 == SND2_TAG \|\| chunk_type == SND1_TAG) && wsvqa->audio_channels == 0) {
	av_log(s, AV_LOG_ERROR, "audio chunk without any audio header information found\n");
	return AVERROR_INVALIDDATA;
	}

	if ((chunk_type == SND1_TAG) \|\| (chunk_type == SND2_TAG) \|\| (chunk_type == VQFR_TAG)) {

	ret= av_get_packet(pb, pkt, chunk_size);
	if (ret<0)
	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 */
	pkt->duration = (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 */
	pkt->duration = AV_RL16(pkt->data) / wsvqa->audio_channels;
	} else {
	pkt->stream_index = wsvqa->video_stream_index;
	pkt->duration = 1;
	}
	/* stay on 16-bit alignment */
	if (skip_byte)
	avio_skip(pb, 1);

	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);
	}
	avio_skip(pb, chunk_size + skip_byte);
	}
	}

	return ret;
	}

	AVInputFormat ff_wsvqa_demuxer = {
	.name = "wsvqa",
	.long_name = NULL_IF_CONFIG_SMALL("Westwood Studios VQA format"),
	.priv_data_size = sizeof(WsVqaDemuxContext),
	.read_probe = wsvqa_probe,
	.read_header = wsvqa_read_header,
	.read_packet = wsvqa_read_packet,
	};