libavformat/flacenc.c

   1 /*
   2  * raw FLAC muxer
   3  * Copyright (c) 2006-2009 Justin Ruggles
   4  *
   5  * This file is part of FFmpeg.
   6  *
   7  * FFmpeg is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU Lesser General Public
   9  * License as published by the Free Software Foundation; either
  10  * version 2.1 of the License, or (at your option) any later version.
  11  *
  12  * FFmpeg is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * Lesser General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU Lesser General Public
  18  * License along with FFmpeg; if not, write to the Free Software
  19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  20  */
  21
  22 #include "libavcodec/flac.h"
  23 #include "avformat.h"
  24 #include "flacenc.h"
  25
  26 int ff_flac_write_header(ByteIOContext *pb, AVCodecContext *codec)
  27 {
  28     static const uint8_t header[8] = {
  29         0x66, 0x4C, 0x61, 0x43, 0x80, 0x00, 0x00, 0x22
  30     };
  31     uint8_t *streaminfo;
  32     enum FLACExtradataFormat format;
  33
  34     if (!ff_flac_is_extradata_valid(codec, &format, &streaminfo))
  35         return -1;
  36
  37     /* write "fLaC" stream marker and first metadata block header if needed */
  38     if (format == FLAC_EXTRADATA_FORMAT_STREAMINFO) {
  39         put_buffer(pb, header, 8);
  40     }
  41
  42     /* write STREAMINFO or full header */
  43     put_buffer(pb, codec->extradata, codec->extradata_size);
  44
  45     return 0;
  46 }
  47
  48 static int flac_write_header(struct AVFormatContext *s)
  49 {
  50     return ff_flac_write_header(s->pb, s->streams[0]->codec);
  51 }
  52
  53 static int flac_write_trailer(struct AVFormatContext *s)
  54 {
  55     ByteIOContext *pb = s->pb;
  56     uint8_t *streaminfo;
  57     enum FLACExtradataFormat format;
  58     int64_t file_size;
  59
  60     if (!ff_flac_is_extradata_valid(s->streams[0]->codec, &format, &streaminfo))
  61         return -1;
  62
  63     if (!url_is_streamed(pb)) {
  64         /* rewrite the STREAMINFO header block data */
  65         file_size = url_ftell(pb);
  66         url_fseek(pb, 8, SEEK_SET);
  67         put_buffer(pb, streaminfo, FLAC_STREAMINFO_SIZE);
  68         url_fseek(pb, file_size, SEEK_SET);
  69         put_flush_packet(pb);
  70     } else {
  71         av_log(s, AV_LOG_WARNING, "unable to rewrite FLAC header.\n");
  72     }
  73     return 0;
  74 }
  75
  76 static int flac_write_packet(struct AVFormatContext *s, AVPacket *pkt)
  77 {
  78     put_buffer(s->pb, pkt->data, pkt->size);
  79     put_flush_packet(s->pb);
  80     return 0;
  81 }
  82
  83 AVOutputFormat flac_muxer = {
  84     "flac",
  85     NULL_IF_CONFIG_SMALL("raw FLAC"),
  86     "audio/x-flac",
  87     "flac",
  88     0,
  89     CODEC_ID_FLAC,
  90     CODEC_ID_NONE,
  91     flac_write_header,
  92     flac_write_packet,
  93     flac_write_trailer,
  94     .flags= AVFMT_NOTIMESTAMPS,
  95 };