libavformat/aiffenc.c

   1 /*
   2  * AIFF/AIFF-C muxer
   3  * Copyright (c) 2006  Patrick Guimond
   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 "avformat.h"
  23 #include "aiff.h"
  24
  25 typedef struct {
  26     int64_t form;
  27     int64_t frames;
  28     int64_t ssnd;
  29 } AIFFOutputContext;
  30
  31 static int aiff_write_header(AVFormatContext *s)
  32 {
  33     AIFFOutputContext *aiff = s->priv_data;
  34     ByteIOContext *pb = s->pb;
  35     AVCodecContext *enc = s->streams[0]->codec;
  36     AVExtFloat sample_rate;
  37     int aifc = 0;
  38
  39     /* First verify if format is ok */
  40     if (!enc->codec_tag)
  41         return -1;
  42     if (enc->codec_tag != MKTAG('N','O','N','E'))
  43         aifc = 1;
  44
  45     /* FORM AIFF header */
  46     put_tag(pb, "FORM");
  47     aiff->form = url_ftell(pb);
  48     put_be32(pb, 0);                    /* file length */
  49     put_tag(pb, aifc ? "AIFC" : "AIFF");
  50
  51     if (aifc) { // compressed audio
  52         enc->bits_per_coded_sample = 16;
  53         if (!enc->block_align) {
  54             av_log(s, AV_LOG_ERROR, "block align not set\n");
  55             return -1;
  56         }
  57         /* Version chunk */
  58         put_tag(pb, "FVER");
  59         put_be32(pb, 4);
  60         put_be32(pb, 0xA2805140);
  61     }
  62
  63     /* Common chunk */
  64     put_tag(pb, "COMM");
  65     put_be32(pb, aifc ? 24 : 18); /* size */
  66     put_be16(pb, enc->channels);  /* Number of channels */
  67
  68     aiff->frames = url_ftell(pb);
  69     put_be32(pb, 0);              /* Number of frames */
  70
  71     if (!enc->bits_per_coded_sample)
  72         enc->bits_per_coded_sample = av_get_bits_per_sample(enc->codec_id);
  73     if (!enc->bits_per_coded_sample) {
  74         av_log(s, AV_LOG_ERROR, "could not compute bits per sample\n");
  75         return -1;
  76     }
  77     if (!enc->block_align)
  78         enc->block_align = (enc->bits_per_coded_sample * enc->channels) >> 3;
  79
  80     put_be16(pb, enc->bits_per_coded_sample); /* Sample size */
  81
  82     sample_rate = av_dbl2ext((double)enc->sample_rate);
  83     put_buffer(pb, (uint8_t*)&sample_rate, sizeof(sample_rate));
  84
  85     if (aifc) {
  86         put_le32(pb, enc->codec_tag);
  87         put_be16(pb, 0);
  88     }
  89
  90     /* Sound data chunk */
  91     put_tag(pb, "SSND");
  92     aiff->ssnd = url_ftell(pb);         /* Sound chunk size */
  93     put_be32(pb, 0);                    /* Sound samples data size */
  94     put_be32(pb, 0);                    /* Data offset */
  95     put_be32(pb, 0);                    /* Block-size (block align) */
  96
  97     av_set_pts_info(s->streams[0], 64, 1, s->streams[0]->codec->sample_rate);
  98
  99     /* Data is starting here */
 100     put_flush_packet(pb);
 101
 102     return 0;
 103 }
 104
 105 static int aiff_write_packet(AVFormatContext *s, AVPacket *pkt)
 106 {
 107     ByteIOContext *pb = s->pb;
 108     put_buffer(pb, pkt->data, pkt->size);
 109     return 0;
 110 }
 111
 112 static int aiff_write_trailer(AVFormatContext *s)
 113 {
 114     ByteIOContext *pb = s->pb;
 115     AIFFOutputContext *aiff = s->priv_data;
 116     AVCodecContext *enc = s->streams[0]->codec;
 117
 118     /* Chunks sizes must be even */
 119     int64_t file_size, end_size;
 120     end_size = file_size = url_ftell(pb);
 121     if (file_size & 1) {
 122         put_byte(pb, 0);
 123         end_size++;
 124     }
 125
 126     if (!url_is_streamed(s->pb)) {
 127         /* File length */
 128         url_fseek(pb, aiff->form, SEEK_SET);
 129         put_be32(pb, file_size - aiff->form - 4);
 130
 131         /* Number of sample frames */
 132         url_fseek(pb, aiff->frames, SEEK_SET);
 133         put_be32(pb, (file_size-aiff->ssnd-12)/enc->block_align);
 134
 135         /* Sound Data chunk size */
 136         url_fseek(pb, aiff->ssnd, SEEK_SET);
 137         put_be32(pb, file_size - aiff->ssnd - 4);
 138
 139         /* return to the end */
 140         url_fseek(pb, end_size, SEEK_SET);
 141
 142         put_flush_packet(pb);
 143     }
 144
 145     return 0;
 146 }
 147
 148 AVOutputFormat aiff_muxer = {
 149     "aiff",
 150     NULL_IF_CONFIG_SMALL("Audio IFF"),
 151     "audio/aiff",
 152     "aif,aiff,afc,aifc",
 153     sizeof(AIFFOutputContext),
 154     CODEC_ID_PCM_S16BE,
 155     CODEC_ID_NONE,
 156     aiff_write_header,
 157     aiff_write_packet,
 158     aiff_write_trailer,
 159     .codec_tag= (const AVCodecTag* const []){ff_codec_aiff_tags, 0},
 160 };