diff options
Diffstat (limited to 'ffmpeg/libavformat/westwood_aud.c')
| -rw-r--r-- | ffmpeg/libavformat/westwood_aud.c | 181 |
1 files changed, 0 insertions, 181 deletions
diff --git a/ffmpeg/libavformat/westwood_aud.c b/ffmpeg/libavformat/westwood_aud.c deleted file mode 100644 index f2bd3a1..0000000 --- a/ffmpeg/libavformat/westwood_aud.c +++ /dev/null @@ -1,181 +0,0 @@ -/* - * Westwood Studios AUD 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 AUD 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 - * - * 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/channel_layout.h" -#include "libavutil/intreadwrite.h" -#include "avformat.h" -#include "internal.h" - -#define AUD_HEADER_SIZE 12 -#define AUD_CHUNK_PREAMBLE_SIZE 8 -#define AUD_CHUNK_SIGNATURE 0x0000DEAF - -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; - - if (p->buf[11] != 99 && p->buf[11] != 1) - 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_EXTENSION; -} - -static int wsaud_read_header(AVFormatContext *s) -{ - AVIOContext *pb = s->pb; - AVStream *st; - unsigned char header[AUD_HEADER_SIZE]; - int sample_rate, channels, codec; - - if (avio_read(pb, header, AUD_HEADER_SIZE) != AUD_HEADER_SIZE) - return AVERROR(EIO); - - sample_rate = AV_RL16(&header[0]); - channels = (header[10] & 0x1) + 1; - codec = header[11]; - - /* initialize the audio decoder stream */ - st = avformat_new_stream(s, NULL); - if (!st) - return AVERROR(ENOMEM); - - switch (codec) { - case 1: - if (channels != 1) { - avpriv_request_sample(s, "Stereo WS-SND1"); - return AVERROR_PATCHWELCOME; - } - st->codec->codec_id = AV_CODEC_ID_WESTWOOD_SND1; - break; - case 99: - st->codec->codec_id = AV_CODEC_ID_ADPCM_IMA_WS; - st->codec->bits_per_coded_sample = 4; - st->codec->bit_rate = channels * sample_rate * 4; - break; - default: - avpriv_request_sample(s, "Unknown codec: %d", codec); - return AVERROR_PATCHWELCOME; - } - avpriv_set_pts_info(st, 64, 1, sample_rate); - st->codec->codec_type = AVMEDIA_TYPE_AUDIO; - st->codec->channels = channels; - st->codec->channel_layout = channels == 1 ? AV_CH_LAYOUT_MONO : - AV_CH_LAYOUT_STEREO; - st->codec->sample_rate = sample_rate; - - return 0; -} - -static int wsaud_read_packet(AVFormatContext *s, - AVPacket *pkt) -{ - AVIOContext *pb = s->pb; - unsigned char preamble[AUD_CHUNK_PREAMBLE_SIZE]; - unsigned int chunk_size; - int ret = 0; - AVStream *st = s->streams[0]; - - if (avio_read(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]); - - if (st->codec->codec_id == AV_CODEC_ID_WESTWOOD_SND1) { - /* For Westwood SND1 audio we need to add the output size and input - size to the start of the packet to match what is in VQA. - Specifically, this is needed to signal when a packet should be - decoding as raw 8-bit pcm or variable-size ADPCM. */ - int out_size = AV_RL16(&preamble[2]); - if ((ret = av_new_packet(pkt, chunk_size + 4))) - return ret; - if ((ret = avio_read(pb, &pkt->data[4], chunk_size)) != chunk_size) - return ret < 0 ? ret : AVERROR(EIO); - AV_WL16(&pkt->data[0], out_size); - AV_WL16(&pkt->data[2], chunk_size); - - pkt->duration = out_size; - } else { - ret = av_get_packet(pb, pkt, chunk_size); - if (ret != chunk_size) - return AVERROR(EIO); - - /* 2 samples/byte, 1 or 2 samples per frame depending on stereo */ - pkt->duration = (chunk_size * 2) / st->codec->channels; - } - pkt->stream_index = st->index; - - return ret; -} - -AVInputFormat ff_wsaud_demuxer = { - .name = "wsaud", - .long_name = NULL_IF_CONFIG_SMALL("Westwood Studios audio"), - .read_probe = wsaud_probe, - .read_header = wsaud_read_header, - .read_packet = wsaud_read_packet, -}; |