@@ -80,6 +80,55 @@ typedef struct MP3Context {

     int64_t nb_frames_offset;

 } MP3Context;

+/* insert a dummy frame containing number of frames */

+static void mp3_write_xing(AVFormatContext *s)

+{

+    MP3Context       *mp3 = s->priv_data;

+    AVCodecContext *codec = s->streams[0]->codec;

+    int       bitrate_idx = 1;    // 32 kbps

+    int64_t   xing_offset = (codec->channels == 2) ? 32 : 17;

+    int32_t        header;

+    MPADecodeHeader  mpah;

+    int srate_idx, i, channels;

+

+    if (!s->pb->seekable)

+        return;

+

+    for (i = 0; i < FF_ARRAY_ELEMS(avpriv_mpa_freq_tab); i++)

+        if (avpriv_mpa_freq_tab[i] == codec->sample_rate) {

+            srate_idx = i;

+            break;

+        }

+    if (i == FF_ARRAY_ELEMS(avpriv_mpa_freq_tab)) {

+        av_log(s, AV_LOG_ERROR, "Unsupported sample rate.\n");

+        return;

+    }

+

+    switch (codec->channels) {

+    case 1:  channels = MPA_MONO;                                          break;

+    case 2:  channels = MPA_STEREO;                                        break;

+    default: av_log(s, AV_LOG_ERROR, "Unsupported number of channels.\n"); return;

+    }

+

+    /* dummy MPEG audio header */

+    header  =  0xff                                  << 24; // sync

+    header |= (0x7 << 5 | 0x3 << 3 | 0x1 << 1 | 0x1) << 16; // sync/mpeg-1/layer 3/no crc*/

+    header |= (bitrate_idx << 4 | srate_idx << 2)    <<  8;

+    header |= channels << 6;

+    avio_wb32(s->pb, header);

+

+    avpriv_mpegaudio_decode_header(&mpah, header);

+

+    ffio_fill(s->pb, 0, xing_offset);

+    ffio_wfourcc(s->pb, "Xing");

+    avio_wb32(s->pb, 0x1);    // only number of frames

+    mp3->nb_frames_offset = avio_tell(s->pb);

+    avio_wb32(s->pb, 0);

+

+    mpah.frame_size -= 4 + xing_offset + 4 + 4 + 4;

+    ffio_fill(s->pb, 0, mpah.frame_size);

+}

+

 static int mp3_write_trailer(struct AVFormatContext *s)

 {

     uint8_t buf[ID3v1_TAG_SIZE];

@@ -132,51 +181,6 @@ static const AVClass mp3_muxer_class = {

     .version        = LIBAVUTIL_VERSION_INT,

 };

-/* insert a dummy frame containing number of frames */

-static void mp3_write_xing(AVFormatContext *s)

-{

-    AVCodecContext *codec = s->streams[0]->codec;

-    MP3Context       *mp3 = s->priv_data;

-    int       bitrate_idx = 1;    // 32 kbps

-    int64_t   xing_offset = (codec->channels == 2) ? 32 : 17;

-    int32_t        header;

-    MPADecodeHeader  mpah;

-    int srate_idx, i, channels;

-

-    for (i = 0; i < FF_ARRAY_ELEMS(avpriv_mpa_freq_tab); i++)

-        if (avpriv_mpa_freq_tab[i] == codec->sample_rate) {

-            srate_idx = i;

-            break;

-        }

-    if (i == FF_ARRAY_ELEMS(avpriv_mpa_freq_tab)) {

-        av_log(s, AV_LOG_ERROR, "Unsupported sample rate.\n");

-        return;

-    }

-

-    switch (codec->channels) {

-    case 1:  channels = MPA_MONO;                                          break;

-    case 2:  channels = MPA_STEREO;                                        break;

-    default: av_log(s, AV_LOG_ERROR, "Unsupported number of channels.\n"); return;

-    }

-

-    /* dummy MPEG audio header */

-    header  =  0xff                                  << 24; // sync

-    header |= (0x7 << 5 | 0x3 << 3 | 0x1 << 1 | 0x1) << 16; // sync/mpeg-1/layer 3/no crc*/

-    header |= (bitrate_idx << 4 | srate_idx << 2)    <<  8;

-    header |= channels << 6;

-    avio_wb32(s->pb, header);

-

-    avpriv_mpegaudio_decode_header(&mpah, header);

-

-    ffio_fill(s->pb, 0, xing_offset);

-    ffio_wfourcc(s->pb, "Xing");

-    avio_wb32(s->pb, 0x1);    // only number of frames

-    mp3->nb_frames_offset = avio_tell(s->pb);

-    avio_wb32(s->pb, 0);

-

-    mpah.frame_size -= 4 + xing_offset + 4 + 4 + 4;

-    ffio_fill(s->pb, 0, mpah.frame_size);

-}

 /**

  * Write an ID3v2 header at beginning of stream