yading@11: /*
yading@11:  * raw FLAC muxer
yading@11:  * Copyright (c) 2006-2009 Justin Ruggles
yading@11:  *
yading@11:  * This file is part of FFmpeg.
yading@11:  *
yading@11:  * FFmpeg is free software; you can redistribute it and/or
yading@11:  * modify it under the terms of the GNU Lesser General Public
yading@11:  * License as published by the Free Software Foundation; either
yading@11:  * version 2.1 of the License, or (at your option) any later version.
yading@11:  *
yading@11:  * FFmpeg is distributed in the hope that it will be useful,
yading@11:  * but WITHOUT ANY WARRANTY; without even the implied warranty of
yading@11:  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
yading@11:  * Lesser General Public License for more details.
yading@11:  *
yading@11:  * You should have received a copy of the GNU Lesser General Public
yading@11:  * License along with FFmpeg; if not, write to the Free Software
yading@11:  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
yading@11:  */
yading@11: 
yading@11: #include "libavcodec/flac.h"
yading@11: #include "avformat.h"
yading@11: #include "flacenc.h"
yading@11: #include "vorbiscomment.h"
yading@11: #include "libavcodec/bytestream.h"
yading@11: 
yading@11: 
yading@11: static int flac_write_block_padding(AVIOContext *pb, unsigned int n_padding_bytes,
yading@11:                                     int last_block)
yading@11: {
yading@11:     avio_w8(pb, last_block ? 0x81 : 0x01);
yading@11:     avio_wb24(pb, n_padding_bytes);
yading@11:     while (n_padding_bytes > 0) {
yading@11:         avio_w8(pb, 0);
yading@11:         n_padding_bytes--;
yading@11:     }
yading@11:     return 0;
yading@11: }
yading@11: 
yading@11: static int flac_write_block_comment(AVIOContext *pb, AVDictionary **m,
yading@11:                                     int last_block, int bitexact)
yading@11: {
yading@11:     const char *vendor = bitexact ? "ffmpeg" : LIBAVFORMAT_IDENT;
yading@11:     unsigned int len, count;
yading@11:     uint8_t *p, *p0;
yading@11: 
yading@11:     ff_metadata_conv(m, ff_vorbiscomment_metadata_conv, NULL);
yading@11: 
yading@11:     len = ff_vorbiscomment_length(*m, vendor, &count);
yading@11:     p0 = av_malloc(len+4);
yading@11:     if (!p0)
yading@11:         return AVERROR(ENOMEM);
yading@11:     p = p0;
yading@11: 
yading@11:     bytestream_put_byte(&p, last_block ? 0x84 : 0x04);
yading@11:     bytestream_put_be24(&p, len);
yading@11:     ff_vorbiscomment_write(&p, m, vendor, count);
yading@11: 
yading@11:     avio_write(pb, p0, len+4);
yading@11:     av_freep(&p0);
yading@11:     p = NULL;
yading@11: 
yading@11:     return 0;
yading@11: }
yading@11: 
yading@11: static int flac_write_header(struct AVFormatContext *s)
yading@11: {
yading@11:     int ret;
yading@11:     AVCodecContext *codec = s->streams[0]->codec;
yading@11: 
yading@11:     if (s->nb_streams > 1) {
yading@11:         av_log(s, AV_LOG_ERROR, "only one stream is supported\n");
yading@11:         return AVERROR(EINVAL);
yading@11:     }
yading@11:     if (codec->codec_id != AV_CODEC_ID_FLAC) {
yading@11:         av_log(s, AV_LOG_ERROR, "unsupported codec\n");
yading@11:         return AVERROR(EINVAL);
yading@11:     }
yading@11: 
yading@11:     ret = ff_flac_write_header(s->pb, codec, 0);
yading@11:     if (ret)
yading@11:         return ret;
yading@11: 
yading@11:     ret = flac_write_block_comment(s->pb, &s->metadata, 0,
yading@11:                                    codec->flags & CODEC_FLAG_BITEXACT);
yading@11:     if (ret)
yading@11:         return ret;
yading@11: 
yading@11:     /* The command line flac encoder defaults to placing a seekpoint
yading@11:      * every 10s.  So one might add padding to allow that later
yading@11:      * but there seems to be no simple way to get the duration here.
yading@11:      * So let's try the flac default of 8192 bytes */
yading@11:     flac_write_block_padding(s->pb, 8192, 1);
yading@11: 
yading@11:     return ret;
yading@11: }
yading@11: 
yading@11: static int flac_write_trailer(struct AVFormatContext *s)
yading@11: {
yading@11:     AVIOContext *pb = s->pb;
yading@11:     uint8_t *streaminfo;
yading@11:     enum FLACExtradataFormat format;
yading@11:     int64_t file_size;
yading@11: 
yading@11:     if (!avpriv_flac_is_extradata_valid(s->streams[0]->codec, &format, &streaminfo))
yading@11:         return -1;
yading@11: 
yading@11:     if (pb->seekable) {
yading@11:         /* rewrite the STREAMINFO header block data */
yading@11:         file_size = avio_tell(pb);
yading@11:         avio_seek(pb, 8, SEEK_SET);
yading@11:         avio_write(pb, streaminfo, FLAC_STREAMINFO_SIZE);
yading@11:         avio_seek(pb, file_size, SEEK_SET);
yading@11:         avio_flush(pb);
yading@11:     } else {
yading@11:         av_log(s, AV_LOG_WARNING, "unable to rewrite FLAC header.\n");
yading@11:     }
yading@11:     return 0;
yading@11: }
yading@11: 
yading@11: static int flac_write_packet(struct AVFormatContext *s, AVPacket *pkt)
yading@11: {
yading@11:     avio_write(s->pb, pkt->data, pkt->size);
yading@11:     return 0;
yading@11: }
yading@11: 
yading@11: AVOutputFormat ff_flac_muxer = {
yading@11:     .name              = "flac",
yading@11:     .long_name         = NULL_IF_CONFIG_SMALL("raw FLAC"),
yading@11:     .mime_type         = "audio/x-flac",
yading@11:     .extensions        = "flac",
yading@11:     .audio_codec       = AV_CODEC_ID_FLAC,
yading@11:     .video_codec       = AV_CODEC_ID_NONE,
yading@11:     .write_header      = flac_write_header,
yading@11:     .write_packet      = flac_write_packet,
yading@11:     .write_trailer     = flac_write_trailer,
yading@11:     .flags             = AVFMT_NOTIMESTAMPS,
yading@11: };