making act segmenter

1 files changed, 140 insertions, 0 deletions

diff --git a/ffmpeg/libavformat/flacenc.c b/ffmpeg/libavformat/flacenc.c
new file mode 100644
index 0000000..b625278
--- /dev/null
+++ b/ffmpeg/libavformat/flacenc.c
@@ -0,0 +1,140 @@
+/*
+ * raw FLAC muxer
+ * Copyright (c) 2006-2009 Justin Ruggles
+ *
+ * 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 "libavcodec/flac.h"
+#include "avformat.h"
+#include "flacenc.h"
+#include "vorbiscomment.h"
+#include "libavcodec/bytestream.h"
+
+
+static int flac_write_block_padding(AVIOContext *pb, unsigned int n_padding_bytes,
+                                    int last_block)
+{
+    avio_w8(pb, last_block ? 0x81 : 0x01);
+    avio_wb24(pb, n_padding_bytes);
+    while (n_padding_bytes > 0) {
+        avio_w8(pb, 0);
+        n_padding_bytes--;
+    }
+    return 0;
+}
+
+static int flac_write_block_comment(AVIOContext *pb, AVDictionary **m,
+                                    int last_block, int bitexact)
+{
+    const char *vendor = bitexact ? "ffmpeg" : LIBAVFORMAT_IDENT;
+    unsigned int len, count;
+    uint8_t *p, *p0;
+
+    ff_metadata_conv(m, ff_vorbiscomment_metadata_conv, NULL);
+
+    len = ff_vorbiscomment_length(*m, vendor, &count);
+    p0 = av_malloc(len+4);
+    if (!p0)
+        return AVERROR(ENOMEM);
+    p = p0;
+
+    bytestream_put_byte(&p, last_block ? 0x84 : 0x04);
+    bytestream_put_be24(&p, len);
+    ff_vorbiscomment_write(&p, m, vendor, count);
+
+    avio_write(pb, p0, len+4);
+    av_freep(&p0);
+    p = NULL;
+
+    return 0;
+}
+
+static int flac_write_header(struct AVFormatContext *s)
+{
+    int ret;
+    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 != AV_CODEC_ID_FLAC) {
+        av_log(s, AV_LOG_ERROR, "unsupported codec\n");
+        return AVERROR(EINVAL);
+    }
+
+    ret = ff_flac_write_header(s->pb, codec, 0);
+    if (ret)
+        return ret;
+
+    ret = flac_write_block_comment(s->pb, &s->metadata, 0,
+                                   codec->flags & CODEC_FLAG_BITEXACT);
+    if (ret)
+        return ret;
+
+    /* The command line flac encoder defaults to placing a seekpoint
+     * every 10s.  So one might add padding to allow that later
+     * but there seems to be no simple way to get the duration here.
+     * So let's try the flac default of 8192 bytes */
+    flac_write_block_padding(s->pb, 8192, 1);
+
+    return ret;
+}
+
+static int flac_write_trailer(struct AVFormatContext *s)
+{
+    AVIOContext *pb = s->pb;
+    uint8_t *streaminfo;
+    enum FLACExtradataFormat format;
+    int64_t file_size;
+
+    if (!avpriv_flac_is_extradata_valid(s->streams[0]->codec, &format, &streaminfo))
+        return -1;
+
+    if (pb->seekable) {
+        /* rewrite the STREAMINFO header block data */
+        file_size = avio_tell(pb);
+        avio_seek(pb, 8, SEEK_SET);
+        avio_write(pb, streaminfo, FLAC_STREAMINFO_SIZE);
+        avio_seek(pb, file_size, SEEK_SET);
+        avio_flush(pb);
+    } else {
+        av_log(s, AV_LOG_WARNING, "unable to rewrite FLAC header.\n");
+    }
+    return 0;
+}
+
+static int flac_write_packet(struct AVFormatContext *s, AVPacket *pkt)
+{
+    avio_write(s->pb, pkt->data, pkt->size);
+    avio_flush(s->pb);
+    return 0;
+}
+
+AVOutputFormat ff_flac_muxer = {
+    .name              = "flac",
+    .long_name         = NULL_IF_CONFIG_SMALL("raw FLAC"),
+    .mime_type         = "audio/x-flac",
+    .extensions        = "flac",
+    .audio_codec       = AV_CODEC_ID_FLAC,
+    .video_codec       = AV_CODEC_ID_NONE,
+    .write_header      = flac_write_header,
+    .write_packet      = flac_write_packet,
+    .write_trailer     = flac_write_trailer,
+    .flags             = AVFMT_NOTIMESTAMPS,
+};