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#include "metadata.h" 26#include "vorbiscomment.h" 27#include "libavcodec/bytestream.h" 28 29 30static int flac_write_block_padding(ByteIOContext *pb, unsigned int n_padding_bytes, 31 int last_block) 32{ 33 put_byte(pb, last_block ? 0x81 : 0x01); 34 put_be24(pb, n_padding_bytes); 35 while (n_padding_bytes > 0) { 36 put_byte(pb, 0); 37 n_padding_bytes--; 38 } 39 return 0; 40} 41 42static int flac_write_block_comment(ByteIOContext *pb, AVMetadata *m, 43 int last_block, int bitexact) 44{ 45 const char *vendor = bitexact ? "ffmpeg" : LIBAVFORMAT_IDENT; 46 unsigned int len, count; 47 uint8_t *p, *p0; 48 49 len = ff_vorbiscomment_length(m, vendor, &count); 50 p0 = av_malloc(len+4); 51 if (!p0) 52 return AVERROR(ENOMEM); 53 p = p0; 54 55 bytestream_put_byte(&p, last_block ? 0x84 : 0x04); 56 bytestream_put_be24(&p, len); 57 ff_vorbiscomment_write(&p, m, vendor, count); 58 59 put_buffer(pb, p0, len+4); 60 av_freep(&p0); 61 p = NULL; 62 63 return 0; 64} 65 66static int flac_write_header(struct AVFormatContext *s) 67{ 68 int ret; 69 AVCodecContext *codec = s->streams[0]->codec; 70 71 ret = ff_flac_write_header(s->pb, codec, 0); 72 if (ret) 73 return ret; 74 75 ret = flac_write_block_comment(s->pb, s->metadata, 0, 76 codec->flags & CODEC_FLAG_BITEXACT); 77 if (ret) 78 return ret; 79 80 /* The command line flac encoder defaults to placing a seekpoint 81 * every 10s. So one might add padding to allow that later 82 * but there seems to be no simple way to get the duration here. 83 * So let's try the flac default of 8192 bytes */ 84 flac_write_block_padding(s->pb, 8192, 1); 85 86 return ret; 87} 88 89static int flac_write_trailer(struct AVFormatContext *s) 90{ 91 ByteIOContext *pb = s->pb; 92 uint8_t *streaminfo; 93 enum FLACExtradataFormat format; 94 int64_t file_size; 95 96 if (!ff_flac_is_extradata_valid(s->streams[0]->codec, &format, &streaminfo)) 97 return -1; 98 99 if (!url_is_streamed(pb)) { 100 /* rewrite the STREAMINFO header block data */ 101 file_size = url_ftell(pb); 102 url_fseek(pb, 8, SEEK_SET); 103 put_buffer(pb, streaminfo, FLAC_STREAMINFO_SIZE); 104 url_fseek(pb, file_size, SEEK_SET); 105 put_flush_packet(pb); 106 } else { 107 av_log(s, AV_LOG_WARNING, "unable to rewrite FLAC header.\n"); 108 } 109 return 0; 110} 111 112static int flac_write_packet(struct AVFormatContext *s, AVPacket *pkt) 113{ 114 put_buffer(s->pb, pkt->data, pkt->size); 115 put_flush_packet(s->pb); 116 return 0; 117} 118 119AVOutputFormat flac_muxer = { 120 "flac", 121 NULL_IF_CONFIG_SMALL("raw FLAC"), 122 "audio/x-flac", 123 "flac", 124 0, 125 CODEC_ID_FLAC, 126 CODEC_ID_NONE, 127 flac_write_header, 128 flac_write_packet, 129 flac_write_trailer, 130 .flags= AVFMT_NOTIMESTAMPS, 131 .metadata_conv = ff_vorbiscomment_metadata_conv, 132}; 133