/*

  * AU muxer and demuxer

  * Copyright (c) 2001 Fabrice Bellard

  *

  * first version by Francois Revol <revol@free.fr>
  *

  * 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

  */
 
 /*
  * Reference documents:
  * http://www.opengroup.org/public/pubs/external/auformat.html
  * http://www.goice.co.jp/member/mo/formats/au.html
  */
 
 #include "avformat.h"

 #include "internal.h"

 #include "avio_internal.h"

 #include "pcm.h"

 #include "libavutil/avassert.h"

 
 /* if we don't know the size in advance */

 #define AU_UNKNOWN_SIZE ((uint32_t)(~0))

 /* the specification requires an annotation field of at least eight bytes */
 #define AU_HEADER_SIZE (24+8)

 static const AVCodecTag codec_au_tags[] = {

     { AV_CODEC_ID_PCM_MULAW,  1 },
     { AV_CODEC_ID_PCM_S8,     2 },
     { AV_CODEC_ID_PCM_S16BE,  3 },
     { AV_CODEC_ID_PCM_S24BE,  4 },
     { AV_CODEC_ID_PCM_S32BE,  5 },
     { AV_CODEC_ID_PCM_F32BE,  6 },
     { AV_CODEC_ID_PCM_F64BE,  7 },

     { AV_CODEC_ID_ADPCM_G726LE, 23 },

     { AV_CODEC_ID_ADPCM_G722,24 },

     { AV_CODEC_ID_ADPCM_G726LE, 25 },
     { AV_CODEC_ID_ADPCM_G726LE, 26 },

     { AV_CODEC_ID_PCM_ALAW,  27 },

     { AV_CODEC_ID_ADPCM_G726LE, MKBETAG('7','2','6','2') },

     { AV_CODEC_ID_NONE,       0 },

 };
 

 #if CONFIG_AU_DEMUXER

 static int au_probe(AVProbeData *p)
 {
     if (p->buf[0] == '.' && p->buf[1] == 's' &&
         p->buf[2] == 'n' && p->buf[3] == 'd')
         return AVPROBE_SCORE_MAX;
     else
         return 0;
 }
 

 #define BLOCK_SIZE 1024
 

 static int au_read_header(AVFormatContext *s)

 {

     int size, data_size = 0;

     unsigned int tag;

     AVIOContext *pb = s->pb;

     unsigned int id, channels, rate;

     int bps;

     enum AVCodecID codec;

     AVStream *st;
 

     tag = avio_rl32(pb);

     if (tag != MKTAG('.', 's', 'n', 'd'))

         return AVERROR_INVALIDDATA;

     size = avio_rb32(pb); /* header size */

     data_size = avio_rb32(pb); /* data size in bytes */
 

     if (data_size < 0 && data_size != AU_UNKNOWN_SIZE) {

         av_log(s, AV_LOG_ERROR, "Invalid negative data size '%d' found\n", data_size);
         return AVERROR_INVALIDDATA;
     }

     id       = avio_rb32(pb);
     rate     = avio_rb32(pb);

     channels = avio_rb32(pb);

     if (size > 24) {
         /* skip unused data */
         avio_skip(pb, size - 24);
     }
 

     codec = ff_codec_get_id(codec_au_tags, id);

     if (codec == AV_CODEC_ID_NONE) {

         avpriv_request_sample(s, "unknown or unsupported codec tag: %u", id);

         return AVERROR_PATCHWELCOME;
     }
 
     bps = av_get_bits_per_sample(codec);

     if (codec == AV_CODEC_ID_ADPCM_G726LE) {
         if (id == MKBETAG('7','2','6','2')) {
             bps = 2;
         } else {
             const uint8_t bpcss[] = {4, 0, 3, 5};

             av_assert0(id >= 23 && id < 23 + 4);

             bps = bpcss[id - 23];
         }
     } else if (!bps) {

         avpriv_request_sample(s, "Unknown bits per sample");

         return AVERROR_PATCHWELCOME;

     }
 

     if (channels == 0 || channels >= INT_MAX / (BLOCK_SIZE * bps >> 3)) {

         av_log(s, AV_LOG_ERROR, "Invalid number of channels %u\n", channels);

         return AVERROR_INVALIDDATA;
     }
 

     if (rate == 0 || rate > INT_MAX) {
         av_log(s, AV_LOG_ERROR, "Invalid sample rate: %u\n", rate);

         return AVERROR_INVALIDDATA;
     }
 

     st = avformat_new_stream(s, NULL);

     if (!st)

         return AVERROR(ENOMEM);

     st->codec->codec_type  = AVMEDIA_TYPE_AUDIO;
     st->codec->codec_tag   = id;
     st->codec->codec_id    = codec;
     st->codec->channels    = channels;

     st->codec->sample_rate = rate;

     st->codec->bits_per_coded_sample = bps;

     st->codec->bit_rate    = channels * rate * bps;

     st->codec->block_align = FFMAX(bps * st->codec->channels / 8, 1);

     if (data_size != AU_UNKNOWN_SIZE)

     st->duration = (((int64_t)data_size)<<3) / (st->codec->channels * (int64_t)bps);

 
     st->start_time = 0;

     avpriv_set_pts_info(st, 64, 1, rate);

     return 0;
 }
 

 AVInputFormat ff_au_demuxer = {

     .name        = "au",
     .long_name   = NULL_IF_CONFIG_SMALL("Sun AU"),
     .read_probe  = au_probe,
     .read_header = au_read_header,

     .read_packet = ff_pcm_read_packet,

     .read_seek   = ff_pcm_read_seek,
     .codec_tag   = (const AVCodecTag* const []) { codec_au_tags, 0 },

 };

 #endif /* CONFIG_AU_DEMUXER */

 #if CONFIG_AU_MUXER

 #include "rawenc.h"
 

 static int au_write_header(AVFormatContext *s)

 {

     AVIOContext *pb = s->pb;
     AVCodecContext *enc = s->streams[0]->codec;
 

     if (s->nb_streams != 1) {
         av_log(s, AV_LOG_ERROR, "only one stream is supported\n");

         return AVERROR(EINVAL);

     }
 
     enc->codec_tag = ff_codec_get_tag(codec_au_tags, enc->codec_id);
     if (!enc->codec_tag) {
         av_log(s, AV_LOG_ERROR, "unsupported codec\n");
         return AVERROR(EINVAL);
     }

 
     ffio_wfourcc(pb, ".snd");                   /* magic number */

     avio_wb32(pb, AU_HEADER_SIZE);              /* header size */

     avio_wb32(pb, AU_UNKNOWN_SIZE);             /* data size */

     avio_wb32(pb, enc->codec_tag);              /* codec ID */

     avio_wb32(pb, enc->sample_rate);

     avio_wb32(pb, enc->channels);

     avio_wb64(pb, 0); /* annotation field */

     avio_flush(pb);
 
     return 0;
 }
 
 static int au_write_trailer(AVFormatContext *s)
 {
     AVIOContext *pb = s->pb;

     int64_t file_size = avio_tell(pb);

     if (s->pb->seekable && file_size < INT32_MAX) {

         /* update file size */
         avio_seek(pb, 8, SEEK_SET);

         avio_wb32(pb, (uint32_t)(file_size - AU_HEADER_SIZE));

         avio_seek(pb, file_size, SEEK_SET);
         avio_flush(pb);
     }
 
     return 0;
 }
 

 AVOutputFormat ff_au_muxer = {

     .name          = "au",
     .long_name     = NULL_IF_CONFIG_SMALL("Sun AU"),
     .mime_type     = "audio/basic",
     .extensions    = "au",
     .audio_codec   = AV_CODEC_ID_PCM_S16BE,
     .video_codec   = AV_CODEC_ID_NONE,
     .write_header  = au_write_header,
     .write_packet  = ff_raw_write_packet,
     .write_trailer = au_write_trailer,
     .codec_tag     = (const AVCodecTag* const []) { codec_au_tags, 0 },

 };

 #endif /* CONFIG_AU_MUXER */