return count;
}
+#define XING_NUM_BAGS 400
+#define XING_TOC_SIZE 100
+// maximum size of the xing frame: offset/Xing/flags/frames/size/TOC
+#define XING_MAX_SIZE (32 + 4 + 4 + 4 + 4 + XING_TOC_SIZE)
+
typedef struct MP3Context {
const AVClass *class;
ID3v2EncContext id3;
int id3v2_version;
int write_id3v1;
- int64_t nb_frames_offset;
+ int write_xing;
+
+ /* xing header */
+ int64_t xing_offset;
+ int32_t frames;
+ int32_t size;
+ uint32_t want;
+ uint32_t seen;
+ uint32_t pos;
+ uint64_t bag[XING_NUM_BAGS];
+ int initial_bitrate;
+ int has_variable_bitrate;
/* index of the audio stream */
int audio_stream_idx;
static const uint8_t xing_offtbl[2][2] = {{32, 17}, {17, 9}};
-/* insert a dummy frame containing number of frames */
+/*
+ * Write an empty XING header and initialize respective data.
+ */
static void mp3_write_xing(AVFormatContext *s)
{
MP3Context *mp3 = s->priv_data;
AVCodecContext *codec = s->streams[mp3->audio_stream_idx]->codec;
- int bitrate_idx = 1; // 32 kbps
int32_t header;
MPADecodeHeader mpah;
int srate_idx, i, channels;
+ int bitrate_idx;
int xing_offset;
int ver = 0;
- if (!s->pb->seekable)
+ if (!s->pb->seekable || !mp3->write_xing)
return;
for (i = 0; i < FF_ARRAY_ELEMS(avpriv_mpa_freq_tab); i++) {
return;
}
+ /* 64 kbps frame, should be large enough */
+ bitrate_idx = (ver == 3) ? 5 : 8;
+
/* dummy MPEG audio header */
header = 0xff << 24; // sync
header |= (0x7 << 5 | ver << 3 | 0x1 << 1 | 0x1) << 16; // sync/audio-version/layer 3/no crc*/
avpriv_mpegaudio_decode_header(&mpah, header);
+ av_assert0(mpah.frame_size >= XING_MAX_SIZE);
+
xing_offset = xing_offtbl[ver != 3][codec->channels == 1];
ffio_fill(s->pb, 0, xing_offset);
+ mp3->xing_offset = avio_tell(s->pb);
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);
+ avio_wb32(s->pb, 0x01 | 0x02 | 0x04); // frames / size / TOC
+
+ mp3->size = mpah.frame_size;
+ mp3->want = 1;
+
+ avio_wb32(s->pb, 0); // frames
+ avio_wb32(s->pb, 0); // size
- mpah.frame_size -= 4 + xing_offset + 4 + 4 + 4;
+ // TOC
+ for (i = 0; i < XING_TOC_SIZE; i++)
+ avio_w8(s->pb, 255 * i / XING_TOC_SIZE);
+
+ mpah.frame_size -= 4 + xing_offset + 4 + 4 + 4 + 4 + XING_TOC_SIZE;
ffio_fill(s->pb, 0, mpah.frame_size);
}
+/*
+ * Add a frame to XING data.
+ * Following lame's "VbrTag.c".
+ */
+static void mp3_xing_add_frame(MP3Context *mp3, AVPacket *pkt)
+{
+ int i;
+
+ mp3->frames++;
+ mp3->seen++;
+ mp3->size += pkt->size;
+
+ if (mp3->want == mp3->seen) {
+ mp3->bag[mp3->pos] = mp3->size;
+
+ if (XING_NUM_BAGS == ++mp3->pos) {
+ /* shrink table to half size by throwing away each second bag. */
+ for (i = 1; i < XING_NUM_BAGS; i += 2)
+ mp3->bag[i / 2] = mp3->bag[i];
+
+ /* double wanted amount per bag. */
+ mp3->want *= 2;
+ /* adjust current position to half of table size. */
+ mp3->pos = XING_NUM_BAGS / 2;
+ }
+
+ mp3->seen = 0;
+ }
+}
+
+static int mp3_write_audio_packet(AVFormatContext *s, AVPacket *pkt)
+{
+ MP3Context *mp3 = s->priv_data;
+
+ if (mp3->xing_offset && pkt->size >= 4) {
+ MPADecodeHeader c;
+
+ avpriv_mpegaudio_decode_header(&c, AV_RB32(pkt->data));
+
+ if (!mp3->initial_bitrate)
+ mp3->initial_bitrate = c.bit_rate;
+ if ((c.bit_rate == 0) || (mp3->initial_bitrate != c.bit_rate))
+ mp3->has_variable_bitrate = 1;
+
+ mp3_xing_add_frame(mp3, pkt);
+ }
+
+ return ff_raw_write_packet(s, pkt);
+}
+
static int mp3_queue_flush(AVFormatContext *s)
{
MP3Context *mp3 = s->priv_data;
mp3_write_xing(s);
while ((pktl = mp3->queue)) {
- if (write && (ret = ff_raw_write_packet(s, &pktl->pkt)) < 0)
+ if (write && (ret = mp3_write_audio_packet(s, &pktl->pkt)) < 0)
write = 0;
av_free_packet(&pktl->pkt);
mp3->queue = pktl->next;
return ret;
}
+static void mp3_update_xing(AVFormatContext *s)
+{
+ MP3Context *mp3 = s->priv_data;
+ int i;
+
+ /* replace "Xing" identification string with "Info" for CBR files. */
+ if (!mp3->has_variable_bitrate) {
+ avio_seek(s->pb, mp3->xing_offset, SEEK_SET);
+ ffio_wfourcc(s->pb, "Info");
+ }
+
+ avio_seek(s->pb, mp3->xing_offset + 8, SEEK_SET);
+ avio_wb32(s->pb, mp3->frames);
+ avio_wb32(s->pb, mp3->size);
+
+ avio_w8(s->pb, 0); // first toc entry has to be zero.
+
+ for (i = 1; i < XING_TOC_SIZE; ++i) {
+ int j = i * mp3->pos / XING_TOC_SIZE;
+ int seek_point = 256LL * mp3->bag[j] / mp3->size;
+ avio_w8(s->pb, FFMIN(seek_point, 255));
+ }
+
+ avio_seek(s->pb, 0, SEEK_END);
+}
+
static int mp3_write_trailer(struct AVFormatContext *s)
{
uint8_t buf[ID3v1_TAG_SIZE];
MP3Context *mp3 = s->priv_data;
- if (mp3 && mp3->pics_to_write) {
+ if (mp3->pics_to_write) {
av_log(s, AV_LOG_WARNING, "No packets were sent for some of the "
"attached pictures.\n");
mp3_queue_flush(s);
}
/* write the id3v1 tag */
- if (mp3 && mp3->write_id3v1 && id3v1_create_tag(s, buf) > 0) {
+ if (mp3->write_id3v1 && id3v1_create_tag(s, buf) > 0) {
avio_write(s->pb, buf, ID3v1_TAG_SIZE);
}
- /* write number of frames */
- if (mp3 && mp3->nb_frames_offset) {
- avio_seek(s->pb, mp3->nb_frames_offset, SEEK_SET);
- avio_wb32(s->pb, s->streams[mp3->audio_stream_idx]->nb_frames);
- avio_seek(s->pb, 0, SEEK_END);
- }
-
- avio_flush(s->pb);
+ if (mp3->xing_offset)
+ mp3_update_xing(s);
return 0;
}
.name = "mp2",
.long_name = NULL_IF_CONFIG_SMALL("MP2 (MPEG audio layer 2)"),
.mime_type = "audio/x-mpeg",
- .extensions = "mp2,m2a",
+ .extensions = "mp2,m2a,mpa",
.audio_codec = AV_CODEC_ID_MP2,
.video_codec = AV_CODEC_ID_NONE,
.write_packet = ff_raw_write_packet,
- .write_trailer = mp3_write_trailer,
.flags = AVFMT_NOTIMESTAMPS,
};
#endif
static const AVOption options[] = {
{ "id3v2_version", "Select ID3v2 version to write. Currently 3 and 4 are supported.",
- offsetof(MP3Context, id3v2_version), AV_OPT_TYPE_INT, {.i64 = 4}, 3, 4, AV_OPT_FLAG_ENCODING_PARAM},
+ offsetof(MP3Context, id3v2_version), AV_OPT_TYPE_INT, {.i64 = 4}, 0, 4, AV_OPT_FLAG_ENCODING_PARAM},
{ "write_id3v1", "Enable ID3v1 writing. ID3v1 tags are written in UTF-8 which may not be supported by most software.",
offsetof(MP3Context, write_id3v1), AV_OPT_TYPE_INT, {.i64 = 0}, 0, 1, AV_OPT_FLAG_ENCODING_PARAM},
+ { "write_xing", "Write the Xing header containing file duration.",
+ offsetof(MP3Context, write_xing), AV_OPT_TYPE_INT, {.i64 = 1}, 0, 1, AV_OPT_FLAG_ENCODING_PARAM},
{ NULL },
};
return AVERROR(ENOMEM);
pktl->pkt = *pkt;
- pkt->destruct = NULL;
+ pktl->pkt.buf = av_buffer_ref(pkt->buf);
+ if (!pktl->pkt.buf) {
+ av_freep(&pktl);
+ return AVERROR(ENOMEM);
+ }
if (mp3->queue_end)
mp3->queue_end->next = pktl;
mp3->queue = pktl;
mp3->queue_end = pktl;
} else
- return ff_raw_write_packet(s, pkt);
+ return mp3_write_audio_packet(s, pkt);
} else {
int ret;
MP3Context *mp3 = s->priv_data;
int ret, i;
+ if (mp3->id3v2_version &&
+ mp3->id3v2_version != 3 &&
+ mp3->id3v2_version != 4) {
+ av_log(s, AV_LOG_ERROR, "Invalid ID3v2 version requested: %d. Only "
+ "3, 4 or 0 (disabled) are allowed.\n", mp3->id3v2_version);
+ return AVERROR(EINVAL);
+ }
+
/* check the streams -- we want exactly one audio and arbitrary number of
* video (attached pictures) */
mp3->audio_stream_idx = -1;
}
mp3->pics_to_write = s->nb_streams - 1;
- ff_id3v2_start(&mp3->id3, s->pb, mp3->id3v2_version, ID3v2_DEFAULT_MAGIC);
- ret = ff_id3v2_write_metadata(s, &mp3->id3);
- if (ret < 0)
- return ret;
+ if (mp3->pics_to_write && !mp3->id3v2_version) {
+ av_log(s, AV_LOG_ERROR, "Attached pictures were requested, but the "
+ "ID3v2 header is disabled.\n");
+ return AVERROR(EINVAL);
+ }
+
+ if (mp3->id3v2_version) {
+ ff_id3v2_start(&mp3->id3, s->pb, mp3->id3v2_version, ID3v2_DEFAULT_MAGIC);
+ ret = ff_id3v2_write_metadata(s, &mp3->id3);
+ if (ret < 0)
+ return ret;
+ }
if (!mp3->pics_to_write) {
- ff_id3v2_finish(&mp3->id3, s->pb);
+ if (mp3->id3v2_version)
+ ff_id3v2_finish(&mp3->id3, s->pb);
mp3_write_xing(s);
}
projects / ffmpeg / blobdiff