FFmpeg: libavformat/wvenc.c Source File

FFmpeg
wvenc.c
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1 /*
2  * WavPack muxer
3  * Copyright (c) 2013 Konstantin Shishkov <kostya.shishkov@gmail.com>
4  * Copyright (c) 2012 Paul B Mahol
5  *
6  * This file is part of FFmpeg.
7  *
8  * FFmpeg is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU Lesser General Public
10  * License as published by the Free Software Foundation; either
11  * version 2.1 of the License, or (at your option) any later version.
12  *
13  * FFmpeg is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16  * Lesser General Public License for more details.
17  *
18  * You should have received a copy of the GNU Lesser General Public
19  * License along with FFmpeg; if not, write to the Free Software
20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21  */
22 
23 #include "libavutil/attributes.h"
24 
25 #include "apetag.h"
26 #include "avformat.h"
27 #include "wv.h"
28 
29  typedef struct WvMuxContext {
30   int64_t samples;
31 } WvMuxContext;
32 
33  static av_cold int wv_write_header(AVFormatContext *ctx)
34 {
35  if (ctx->nb_streams > 1 ||
36  ctx->streams[0]->codec->codec_id != AV_CODEC_ID_WAVPACK) {
37  av_log(ctx, AV_LOG_ERROR, "This muxer only supports a single WavPack stream.\n");
38  return AVERROR(EINVAL);
39  }
40 
41  return 0;
42 }
43 
44  static int wv_write_packet(AVFormatContext *ctx, AVPacket *pkt)
45 {
46  WvMuxContext *s = ctx->priv_data;
47  WvHeader header;
48  int ret;
49 
50  if (pkt->size < WV_HEADER_SIZE ||
51  (ret = ff_wv_parse_header(&header, pkt->data)) < 0) {
52  av_log(ctx, AV_LOG_ERROR, "Invalid WavPack packet.\n");
53  return AVERROR(EINVAL);
54  }
55  s->samples += header.samples;
56 
57  avio_write(ctx->pb, pkt->data, pkt->size);
58 
59  return 0;
60 }
61 
62  static av_cold int wv_write_trailer(AVFormatContext *ctx)
63 {
64  WvMuxContext *s = ctx->priv_data;
65 
66  /* update total number of samples in the first block */
67  if (ctx->pb->seekable && s->samples &&
68  s->samples < UINT32_MAX) {
69  int64_t pos = avio_tell(ctx->pb);
70  avio_seek(ctx->pb, 12, SEEK_SET);
71  avio_wl32(ctx->pb, s->samples);
72  avio_seek(ctx->pb, pos, SEEK_SET);
73  }
74 
75  ff_ape_write_tag(ctx);
76  return 0;
77 }
78 
79  AVOutputFormat ff_wv_muxer = {
80  .name = "wv",
81  .long_name = NULL_IF_CONFIG_SMALL("raw WavPack"),
82  .mime_type = "audio/x-wavpack",
83  .extensions = "wv",
84  .priv_data_size = sizeof(WvMuxContext),
85  .audio_codec = AV_CODEC_ID_WAVPACK,
86  .video_codec = AV_CODEC_ID_NONE,
87  .write_header = wv_write_header,
88  .write_packet = wv_write_packet,
89  .write_trailer = wv_write_trailer,
90  .flags = AVFMT_NOTIMESTAMPS,
91 };

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