WavPack muxer

2026-04-20 21:00:41 +08:00 · 2012-02-06 19:50:09 +00:00
parent 706bd8ea19
commit a3a0774be8
3 changed files with 99 additions and 1 deletions
--- a/libavformat/wvenc.c
+++ b/libavformat/wvenc.c
@@ -0,0 +1,97 @@
+/*
+ * WavPack muxer
+ * Copyright (c) 2012 Paul B Mahol
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * FFmpeg is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include "avformat.h"
+#include "internal.h"
+#include "avio_internal.h"
+
+typedef struct{
+    uint32_t duration;
+    int off;
+} WVMuxContext;
+
+static int write_header(AVFormatContext *s)
+{
+    WVMuxContext *wc = s->priv_data;
+    AVCodecContext *codec = s->streams[0]->codec;
+
+    if (s->nb_streams > 1) {
+        av_log(s, AV_LOG_ERROR, "only one stream is supported\n");
+        return AVERROR(EINVAL);
+    }
+    if (codec->codec_id != CODEC_ID_WAVPACK) {
+        av_log(s, AV_LOG_ERROR, "unsupported codec\n");
+        return AVERROR(EINVAL);
+    }
+    if (codec->extradata_size > 0) {
+        av_log_missing_feature(s, "remuxing from matroska container", 0);
+        return AVERROR_PATCHWELCOME;
+    }
+    wc->off = codec->channels > 2 ? 4 : 0;
+    avpriv_set_pts_info(s->streams[0], 64, 1, codec->sample_rate);
+
+    return 0;
+}
+
+static int write_packet(AVFormatContext *s, AVPacket *pkt)
+{
+    WVMuxContext *wc = s->priv_data;
+    AVIOContext *pb = s->pb;
+
+    wc->duration += pkt->duration;
+    ffio_wfourcc(pb, "wvpk");
+    avio_wl32(pb, pkt->size + 12 + wc->off);
+    avio_wl16(pb, 0x410);
+    avio_w8(pb, 0);
+    avio_w8(pb, 0);
+    avio_wl32(pb, -1);
+    avio_wl32(pb, pkt->pts);
+    avio_write(s->pb, pkt->data, pkt->size);
+    avio_flush(s->pb);
+
+    return 0;
+}
+
+static int write_trailer(AVFormatContext *s)
+{
+    WVMuxContext *wc = s->priv_data;
+    AVIOContext *pb = s->pb;
+
+    if (pb->seekable) {
+        avio_seek(pb, 12, SEEK_SET);
+        avio_wl32(pb, wc->duration);
+        avio_flush(pb);
+    }
+
+    return 0;
+}
+
+AVOutputFormat ff_wv_muxer = {
+    .name              = "wv",
+    .long_name         = NULL_IF_CONFIG_SMALL("WavPack"),
+    .priv_data_size    = sizeof(WVMuxContext),
+    .extensions        = "wv",
+    .audio_codec       = CODEC_ID_WAVPACK,
+    .video_codec       = CODEC_ID_NONE,
+    .write_header      = write_header,
+    .write_packet      = write_packet,
+    .write_trailer     = write_trailer,
+};