/*
  * MLP and TrueHD demuxer
  * Copyright (c) 2001 Fabrice Bellard
  * Copyright (c) 2005 Alex Beregszaszi
  * Copyright (c) 2015 Carl Eugen Hoyos
  *
  * 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
  */
 
 #include "avformat.h"
 #include "rawdec.h"
 #include "libavutil/intreadwrite.h"
 
 static int av_always_inline mlp_thd_probe(AVProbeData *p, uint32_t sync)
 {
     const uint8_t *buf, *last_buf = p->buf, *end = p->buf + p->buf_size;
     int frames = 0, valid = 0, size = 0;

     int nsubframes = 0;

 
     for (buf = p->buf; buf + 8 <= end; buf++) {
         if (AV_RB32(buf + 4) == sync) {
             frames++;
             if (last_buf + size == buf) {

                 valid += 1 + nsubframes / 8;

             }

             nsubframes = 0;

             last_buf = buf;
             size = (AV_RB16(buf) & 0xfff) * 2;
         } else if (buf - last_buf == size) {

             nsubframes++;

             size += (AV_RB16(buf) & 0xfff) * 2;
         }
     }
     if (valid >= 100)
         return AVPROBE_SCORE_MAX;
     return 0;
 }
 
 #if CONFIG_MLP_DEMUXER
 static int mlp_probe(AVProbeData *p)
 {
     return mlp_thd_probe(p, 0xf8726fbb);
 }
 
 AVInputFormat ff_mlp_demuxer = {
     .name           = "mlp",
     .long_name      = NULL_IF_CONFIG_SMALL("raw MLP"),
     .read_probe     = mlp_probe,
     .read_header    = ff_raw_audio_read_header,
     .read_packet    = ff_raw_read_partial_packet,
     .flags          = AVFMT_GENERIC_INDEX | AVFMT_NOTIMESTAMPS,
     .extensions     = "mlp",
     .raw_codec_id   = AV_CODEC_ID_MLP,
 };
 #endif
 
 #if CONFIG_TRUEHD_DEMUXER
 static int thd_probe(AVProbeData *p)
 {
     return mlp_thd_probe(p, 0xf8726fba);
 }
 
 AVInputFormat ff_truehd_demuxer = {
     .name           = "truehd",
     .long_name      = NULL_IF_CONFIG_SMALL("raw TrueHD"),
     .read_probe     = thd_probe,
     .read_header    = ff_raw_audio_read_header,
     .read_packet    = ff_raw_read_partial_packet,
     .flags          = AVFMT_GENERIC_INDEX | AVFMT_NOTIMESTAMPS,
     .extensions     = "thd",
     .raw_codec_id   = AV_CODEC_ID_TRUEHD,
 };
 #endif