3 * Copyright (c) 2006-2009 Justin Ruggles
5 * This file is part of FFmpeg.
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.
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.
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
22 #include "libavcodec/flac.h"
24 #include "avio_internal.h"
26 #include "vorbiscomment.h"
27 #include "libavcodec/bytestream.h"
30 static int flac_write_block_padding(AVIOContext *pb, unsigned int n_padding_bytes,
33 avio_w8(pb, last_block ? 0x81 : 0x01);
34 avio_wb24(pb, n_padding_bytes);
35 ffio_fill(pb, 0, n_padding_bytes);
39 static int flac_write_block_comment(AVIOContext *pb, AVDictionary **m,
40 int last_block, int bitexact)
42 const char *vendor = bitexact ? "ffmpeg" : LIBAVFORMAT_IDENT;
43 unsigned int len, count;
46 ff_metadata_conv(m, ff_vorbiscomment_metadata_conv, NULL);
48 len = ff_vorbiscomment_length(*m, vendor, &count);
49 p0 = av_malloc(len+4);
51 return AVERROR(ENOMEM);
54 bytestream_put_byte(&p, last_block ? 0x84 : 0x04);
55 bytestream_put_be24(&p, len);
56 ff_vorbiscomment_write(&p, m, vendor, count);
58 avio_write(pb, p0, len+4);
65 static int flac_write_header(struct AVFormatContext *s)
68 AVCodecContext *codec = s->streams[0]->codec;
70 if (s->nb_streams > 1) {
71 av_log(s, AV_LOG_ERROR, "only one stream is supported\n");
72 return AVERROR(EINVAL);
74 if (codec->codec_id != AV_CODEC_ID_FLAC) {
75 av_log(s, AV_LOG_ERROR, "unsupported codec\n");
76 return AVERROR(EINVAL);
79 ret = ff_flac_write_header(s->pb, codec, 0);
83 ret = flac_write_block_comment(s->pb, &s->metadata, 0,
84 codec->flags & CODEC_FLAG_BITEXACT);
88 /* The command line flac encoder defaults to placing a seekpoint
89 * every 10s. So one might add padding to allow that later
90 * but there seems to be no simple way to get the duration here.
91 * So let's try the flac default of 8192 bytes */
92 flac_write_block_padding(s->pb, 8192, 1);
97 static int flac_write_trailer(struct AVFormatContext *s)
99 AVIOContext *pb = s->pb;
101 enum FLACExtradataFormat format;
104 if (!avpriv_flac_is_extradata_valid(s->streams[0]->codec, &format, &streaminfo))
108 /* rewrite the STREAMINFO header block data */
109 file_size = avio_tell(pb);
110 avio_seek(pb, 8, SEEK_SET);
111 avio_write(pb, streaminfo, FLAC_STREAMINFO_SIZE);
112 avio_seek(pb, file_size, SEEK_SET);
115 av_log(s, AV_LOG_WARNING, "unable to rewrite FLAC header.\n");
120 static int flac_write_packet(struct AVFormatContext *s, AVPacket *pkt)
122 avio_write(s->pb, pkt->data, pkt->size);
126 AVOutputFormat ff_flac_muxer = {
128 .long_name = NULL_IF_CONFIG_SMALL("raw FLAC"),
129 .mime_type = "audio/x-flac",
130 .extensions = "flac",
131 .audio_codec = AV_CODEC_ID_FLAC,
132 .video_codec = AV_CODEC_ID_NONE,
133 .write_header = flac_write_header,
134 .write_packet = flac_write_packet,
135 .write_trailer = flac_write_trailer,
136 .flags = AVFMT_NOTIMESTAMPS,