libavformat/soxenc.c

   1 /*
   2  * SoX native format muxer
   3  * Copyright (c) 2009 Daniel Verkamp <daniel@drv.nu>
   4  *
   5  * Based on libSoX sox-fmt.c
   6  * Copyright (c) 2008 robs@users.sourceforge.net
   7  *
   8  * This file is part of FFmpeg.
   9  *
  10  * FFmpeg is free software; you can redistribute it and/or
  11  * modify it under the terms of the GNU Lesser General Public
  12  * License as published by the Free Software Foundation; either
  13  * version 2.1 of the License, or (at your option) any later version.
  14  *
  15  * FFmpeg is distributed in the hope that it will be useful,
  16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  18  * Lesser General Public License for more details.
  19  *
  20  * You should have received a copy of the GNU Lesser General Public
  21  * License along with FFmpeg; if not, write to the Free Software
  22  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  23  */
  24
  25 /**
  26  * SoX native format muxer
  27  * @file libavformat/soxenc.c
  28  * @author Daniel Verkamp
  29  * @sa http://wiki.multimedia.cx/index.php?title=SoX_native_intermediate_format
  30  */
  31
  32 #include "libavutil/intreadwrite.h"
  33 #include "avformat.h"
  34 #include "sox.h"
  35
  36 typedef struct {
  37     int64_t header_size;
  38 } SoXContext;
  39
  40 static int sox_write_header(AVFormatContext *s)
  41 {
  42     SoXContext *sox = s->priv_data;
  43     ByteIOContext *pb = s->pb;
  44     AVCodecContext *enc = s->streams[0]->codec;
  45     AVMetadataTag *comment;
  46     size_t comment_len = 0, comment_size;
  47
  48     comment = av_metadata_get(s->metadata, "comment", NULL, 0);
  49     if (comment)
  50         comment_len = strlen(comment->value);
  51     comment_size = (comment_len + 7) & ~7;
  52
  53     sox->header_size = SOX_FIXED_HDR + comment_size;
  54
  55     if (enc->codec_id == CODEC_ID_PCM_S32LE) {
  56         put_tag(pb, ".SoX");
  57         put_le32(pb, sox->header_size);
  58         put_le64(pb, 0); /* number of samples */
  59         put_le64(pb, av_dbl2int(enc->sample_rate));
  60         put_le32(pb, enc->channels);
  61         put_le32(pb, comment_size);
  62     } else if (enc->codec_id == CODEC_ID_PCM_S32BE) {
  63         put_tag(pb, "XoS.");
  64         put_be32(pb, sox->header_size);
  65         put_be64(pb, 0); /* number of samples */
  66         put_be64(pb, av_dbl2int(enc->sample_rate));
  67         put_be32(pb, enc->channels);
  68         put_be32(pb, comment_size);
  69     } else {
  70         av_log(s, AV_LOG_ERROR, "invalid codec; use pcm_s32le or pcm_s32be\n");
  71         return -1;
  72     }
  73
  74     if (comment_len)
  75         put_buffer(pb, comment->value, comment_len);
  76
  77     for ( ; comment_size > comment_len; comment_len++)
  78         put_byte(pb, 0);
  79
  80     put_flush_packet(pb);
  81
  82     return 0;
  83 }
  84
  85 static int sox_write_packet(AVFormatContext *s, AVPacket *pkt)
  86 {
  87     ByteIOContext *pb = s->pb;
  88     put_buffer(pb, pkt->data, pkt->size);
  89     return 0;
  90 }
  91
  92 static int sox_write_trailer(AVFormatContext *s)
  93 {
  94     SoXContext *sox = s->priv_data;
  95     ByteIOContext *pb = s->pb;
  96     AVCodecContext *enc = s->streams[0]->codec;
  97
  98     if (!url_is_streamed(s->pb)) {
  99         /* update number of samples */
 100         int64_t file_size = url_ftell(pb);
 101         int64_t num_samples = (file_size - sox->header_size - 4LL) >> 2LL;
 102         url_fseek(pb, 8, SEEK_SET);
 103         if (enc->codec_id == CODEC_ID_PCM_S32LE) {
 104             put_le64(pb, num_samples);
 105         } else
 106             put_be64(pb, num_samples);
 107         url_fseek(pb, file_size, SEEK_SET);
 108
 109         put_flush_packet(pb);
 110     }
 111
 112     return 0;
 113 }
 114
 115 AVOutputFormat sox_muxer = {
 116     "sox",
 117     NULL_IF_CONFIG_SMALL("SoX native format"),
 118     NULL,
 119     "sox",
 120     sizeof(SoXContext),
 121     CODEC_ID_PCM_S32LE,
 122     CODEC_ID_NONE,
 123     sox_write_header,
 124     sox_write_packet,
 125     sox_write_trailer,
 126 };