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-rw-r--r--gst/mpegvideoparse/mpegvideoparse.c238
1 files changed, 83 insertions, 155 deletions
diff --git a/gst/mpegvideoparse/mpegvideoparse.c b/gst/mpegvideoparse/mpegvideoparse.c
index 18464507..6c776c54 100644
--- a/gst/mpegvideoparse/mpegvideoparse.c
+++ b/gst/mpegvideoparse/mpegvideoparse.c
@@ -28,17 +28,18 @@
/* FIXME: there are still some things to do in this element.
* + Handle Sequence Display Extension to output the display size
* rather than the encoded size.
- * + Collect a list of regions and the sequence headers that apply
- * to each region so that we properly handle SEQUENCE_END followed
- * by a new sequence.
- * + At least detect when the sequence changes and error out instead.
* + Do all the other stuff (documentation, tests) to get it into
* ugly or good.
* + low priority:
* - handle seeking in raw elementary streams
* - calculate timestamps for all un-timestamped frames, taking into
* account frame re-ordering. Doing this probably requires introducing
- * an extra end-to-end delay, however so might not be really desirable.
+ * an extra end-to-end delay however, so might not be really desirable.
+ * - Collect a list of regions and the sequence headers that apply
+ * to each region so that we properly handle SEQUENCE_END followed
+ * by a new sequence. At the moment, the caps will change if the
+ * sequence changes, but if we then seek to a different spot it might
+ * be wrong. Fortunately almost every stream only has 1 sequence.
*/
GST_DEBUG_CATEGORY_STATIC (mpv_parse_debug);
#define GST_CAT_DEFAULT mpv_parse_debug
@@ -190,150 +191,22 @@ gst_mpegvideoparse_dispose (MpegVideoParse * mpegvideoparse)
gst_buffer_replace (&mpegvideoparse->seq_hdr_buf, NULL);
}
-/* Set the Pixel Aspect Ratio in our hdr from a DAR code in the data */
-static void
-set_par_from_dar (MPEGSeqHdr * hdr, guint8 asr_code)
-{
- /* Pixel_width = DAR_width * display_vertical_size */
- /* Pixel_height = DAR_height * display_horizontal_size */
- switch (asr_code) {
- case 0x02: /* 3:4 DAR = 4:3 pixels */
- hdr->par_w = 4 * hdr->height;
- hdr->par_h = 3 * hdr->width;
- break;
- case 0x03: /* 9:16 DAR */
- hdr->par_w = 16 * hdr->height;
- hdr->par_h = 9 * hdr->width;
- break;
- case 0x04: /* 1:2.21 DAR */
- hdr->par_w = 221 * hdr->height;
- hdr->par_h = 100 * hdr->width;
- break;
- case 0x01: /* Square pixels */
- default:
- hdr->par_w = hdr->par_h = 1;
- break;
- }
-}
-
-static void
-set_fps_from_code (MPEGSeqHdr * hdr, guint8 fps_code)
-{
- const gint framerates[][2] = {
- {30, 1}, {24000, 1001}, {24, 1}, {25, 1},
- {30000, 1001}, {30, 1}, {50, 1}, {60000, 1001},
- {60, 1}, {30, 1}
- };
-
- if (fps_code < 10) {
- hdr->fps_n = framerates[fps_code][0];
- hdr->fps_d = framerates[fps_code][1];
- } else {
- /* Force a valid framerate */
- hdr->fps_n = 30;
- hdr->fps_d = 1;
- }
-}
-
-static void
-mpegvideoparse_parse_seq (MpegVideoParse * mpegvideoparse, GstBuffer * buf)
+static gboolean
+mpegvideoparse_handle_sequence (MpegVideoParse * mpegvideoparse,
+ GstBuffer * buf)
{
MPEGSeqHdr new_hdr;
- guint32 code;
- guint8 dar_idx, fps_idx;
- gint seq_data_length;
- guint32 sync_word = 0xffffffff;
guint8 *cur, *end;
- gboolean constrained_flag;
- gboolean load_intra_flag;
- gboolean load_non_intra_flag;
cur = GST_BUFFER_DATA (buf);
end = GST_BUFFER_DATA (buf) + GST_BUFFER_SIZE (buf);
- if (GST_BUFFER_SIZE (buf) < 12)
- return; /* Too small to be a sequence header */
-
- seq_data_length = 12; /* minimum length. */
-
- /* Skip the sync word */
- cur += 4;
-
- /* Parse the MPEG 1 bits */
- new_hdr.mpeg_version = 1;
-
- code = GST_READ_UINT32_BE (cur);
- new_hdr.width = (code >> 20) & 0xfff;
- new_hdr.height = (code >> 8) & 0xfff;
-
- dar_idx = (code >> 4) & 0xf;
- set_par_from_dar (&new_hdr, dar_idx);
- fps_idx = code & 0xf;
- set_fps_from_code (&new_hdr, fps_idx);
-
- constrained_flag = (cur[7] >> 2) & 0x01;
- load_intra_flag = (cur[7] >> 1) & 0x01;
- if (load_intra_flag) {
- seq_data_length += 64; /* 8 rows of 8 bytes of intra matrix */
- if (GST_BUFFER_SIZE (buf) < seq_data_length)
- return;
- cur += 64;
- }
-
- load_non_intra_flag = cur[7] & 0x01;
- if (load_non_intra_flag) {
- seq_data_length += 64; /* 8 rows of 8 bytes of non-intra matrix */
- if (GST_BUFFER_SIZE (buf) < seq_data_length)
- return;
- cur += 64;
- }
-
- /* Skip the rest of the MPEG-1 header */
- cur += 8;
+ memset (&new_hdr, 0, sizeof (MPEGSeqHdr));
- /* Read MPEG-2 sequence extensions */
- cur = mpeg_find_start_code (&sync_word, cur, end);
- while (cur != NULL) {
- /* Cur points at the last byte of the start code */
- if (cur[0] == MPEG_PACKET_EXTENSION) {
- guint8 ext_code;
-
- if ((end - cur - 1) < 1)
- return; /* short extension packet extension */
-
- ext_code = cur[1] >> 4;
- if (ext_code == MPEG_PACKET_EXT_SEQUENCE) {
- /* Parse a Sequence Extension */
- guint8 horiz_size_ext, vert_size_ext;
- guint8 fps_n_ext, fps_d_ext;
-
- if ((end - cur - 1) < 7)
- /* need at least 10 bytes, minus 3 for the start code 000001 */
- return;
-
- horiz_size_ext = ((cur[2] << 1) & 0x02) | ((cur[3] >> 7) & 0x01);
- vert_size_ext = (cur[3] >> 5) & 0x03;
- fps_n_ext = (cur[6] >> 5) & 0x03;
- fps_d_ext = cur[6] & 0x1f;
-
- new_hdr.fps_n *= (fps_n_ext + 1);
- new_hdr.fps_d *= (fps_d_ext + 1);
- new_hdr.width += (horiz_size_ext << 12);
- new_hdr.height += (vert_size_ext << 12);
- }
-
- new_hdr.mpeg_version = 2;
- }
- cur = mpeg_find_start_code (&sync_word, cur, end);
- }
+ if (G_UNLIKELY (!mpeg_util_parse_sequence_hdr (&new_hdr, cur, end)))
+ return FALSE;
- if (new_hdr.par_w != mpegvideoparse->seq_hdr.par_w ||
- new_hdr.par_h != mpegvideoparse->seq_hdr.par_h ||
- new_hdr.fps_n != mpegvideoparse->seq_hdr.fps_n ||
- new_hdr.fps_d != mpegvideoparse->seq_hdr.fps_d ||
- new_hdr.width != mpegvideoparse->seq_hdr.width ||
- new_hdr.height != mpegvideoparse->seq_hdr.height ||
- new_hdr.mpeg_version != mpegvideoparse->seq_hdr.mpeg_version) {
+ if (memcmp (&mpegvideoparse, &new_hdr, sizeof (MPEGSeqHdr)) != 0) {
GstCaps *caps;
GstBuffer *seq_buf;
@@ -344,7 +217,7 @@ mpegvideoparse_parse_seq (MpegVideoParse * mpegvideoparse, GstBuffer * buf)
gst_buffer_unref (seq_buf);
/* And update the new_hdr into our stored version */
- memcpy (&mpegvideoparse->seq_hdr, &new_hdr, sizeof (MPEGSeqHdr));
+ mpegvideoparse->seq_hdr = new_hdr;
caps = gst_caps_new_simple ("video/mpeg",
"systemstream", G_TYPE_BOOLEAN, FALSE,
@@ -357,8 +230,41 @@ mpegvideoparse_parse_seq (MpegVideoParse * mpegvideoparse, GstBuffer * buf)
"codec_data", GST_TYPE_BUFFER, seq_buf, NULL);
GST_DEBUG ("New mpegvideoparse caps: %" GST_PTR_FORMAT, caps);
- gst_pad_set_caps (mpegvideoparse->srcpad, caps);
+ if (!gst_pad_set_caps (mpegvideoparse->srcpad, caps))
+ return FALSE;
}
+
+ return TRUE;
+}
+
+static gboolean
+mpegvideoparse_handle_picture (MpegVideoParse * mpegvideoparse, GstBuffer * buf)
+{
+ guint8 *cur, *end;
+ guint32 sync_word = 0xffffffff;
+
+ cur = GST_BUFFER_DATA (buf);
+ end = GST_BUFFER_DATA (buf) + GST_BUFFER_SIZE (buf);
+
+ cur = mpeg_util_find_start_code (&sync_word, cur, end);
+ while (cur != NULL) {
+ /* Cur points at the last byte of the start code */
+ if (cur[0] == MPEG_PACKET_PICTURE) {
+ guint8 *pic_data = cur - 3;
+ MPEGPictureHdr hdr;
+
+ /* pic_data points to the first byte of the sync word now */
+ if (!mpeg_util_parse_picture_hdr (&hdr, pic_data, end))
+ return FALSE;
+
+ GST_LOG_OBJECT (mpegvideoparse, "Picture type is %u", hdr.pic_type);
+ /* FIXME: Can use the picture type and number of fields to track a
+ * timestamp */
+ }
+ cur = mpeg_util_find_start_code (&sync_word, cur, end);
+ }
+
+ return TRUE;
}
#if 0
@@ -392,11 +298,11 @@ static GstFlowReturn
mpegvideoparse_drain_avail (MpegVideoParse * mpegvideoparse)
{
MPEGBlockInfo *cur;
- GstBuffer *buf;
+ GstBuffer *buf = NULL;
GstFlowReturn res = GST_FLOW_OK;
cur = mpeg_packetiser_get_block (&mpegvideoparse->packer, &buf);
- while (cur != NULL) {
+ while ((cur != NULL) && (res == GST_FLOW_OK)) {
/* Handle the block */
GST_LOG_OBJECT (mpegvideoparse,
"Have block of size %u with pack_type 0x%02x and flags 0x%02x\n",
@@ -404,7 +310,11 @@ mpegvideoparse_drain_avail (MpegVideoParse * mpegvideoparse)
/* Don't start pushing out buffers until we've seen a sequence header */
if (mpegvideoparse->seq_hdr.mpeg_version == 0) {
- if ((cur->flags & MPEG_BLOCK_FLAG_SEQUENCE) == 0) {
+ if (cur->flags & MPEG_BLOCK_FLAG_SEQUENCE) {
+ /* Found a sequence header */
+ if (!mpegvideoparse_handle_sequence (mpegvideoparse, buf))
+ goto error;
+ } else {
if (buf) {
GST_DEBUG_OBJECT (mpegvideoparse,
"No sequence header yet. Dropping buffer of %u bytes",
@@ -412,9 +322,22 @@ mpegvideoparse_drain_avail (MpegVideoParse * mpegvideoparse)
gst_buffer_unref (buf);
buf = NULL;
}
- } else {
- /* Found a sequence header */
- mpegvideoparse_parse_seq (mpegvideoparse, buf);
+ }
+ }
+
+ if (buf != NULL) {
+ /* If outputting a PICTURE packet, we can calculate the duration
+ and possibly the timestamp */
+ if (cur->flags & MPEG_BLOCK_FLAG_PICTURE) {
+ if (!mpegvideoparse_handle_picture (mpegvideoparse, buf)) {
+ /* Corrupted picture. Drop it. */
+ GST_DEBUG_OBJECT (mpegvideoparse,
+ "Corrupted picture header. Dropping buffer of %u bytes",
+ GST_BUFFER_SIZE (buf));
+ mpegvideoparse->need_discont = TRUE;
+ gst_buffer_unref (buf);
+ buf = NULL;
+ }
}
}
@@ -423,7 +346,9 @@ mpegvideoparse_drain_avail (MpegVideoParse * mpegvideoparse)
"mpegvideoparse: pushing buffer of %u bytes with ts %"
GST_TIME_FORMAT, GST_BUFFER_SIZE (buf),
GST_TIME_ARGS (GST_BUFFER_TIMESTAMP (buf)));
+
gst_buffer_set_caps (buf, GST_PAD_CAPS (mpegvideoparse->srcpad));
+
if (mpegvideoparse->need_discont) {
GST_DEBUG_OBJECT (mpegvideoparse,
"setting discont flag on outgoing buffer");
@@ -431,8 +356,6 @@ mpegvideoparse_drain_avail (MpegVideoParse * mpegvideoparse)
mpegvideoparse->need_discont = FALSE;
}
res = gst_pad_push (mpegvideoparse->srcpad, buf);
- if (res != GST_FLOW_OK)
- break;
}
/* Advance to the next data block */
@@ -441,6 +364,10 @@ mpegvideoparse_drain_avail (MpegVideoParse * mpegvideoparse)
};
return res;
+error:
+ if (buf != NULL)
+ gst_buffer_unref (buf);
+ return GST_FLOW_ERROR;
}
static GstFlowReturn
@@ -459,8 +386,8 @@ gst_mpegvideoparse_chain (GstPad * pad, GstBuffer * buf)
GST_DEBUG_OBJECT (mpegvideoparse,
"mpegvideoparse: received buffer of %u bytes with ts %"
- GST_TIME_FORMAT, GST_BUFFER_SIZE (buf),
- GST_TIME_ARGS (GST_BUFFER_TIMESTAMP (buf)));
+ GST_TIME_FORMAT " and offset %" G_GINT64_FORMAT, GST_BUFFER_SIZE (buf),
+ GST_TIME_ARGS (GST_BUFFER_TIMESTAMP (buf)), GST_BUFFER_OFFSET (buf));
/* If we have an offset, and the incoming offset doesn't match,
or we have a discont, handle it first by flushing out data
@@ -477,6 +404,7 @@ gst_mpegvideoparse_chain (GstPad * pad, GstBuffer * buf)
}
}
+ /* Clear out any existing stuff if the new buffer is discontinuous */
if (have_discont) {
GST_DEBUG_OBJECT (mpegvideoparse, "Have discont packet, draining data");
mpegvideoparse->need_discont = TRUE;
@@ -557,9 +485,10 @@ mpv_parse_sink_event (GstPad * pad, GstEvent * event)
gst_event_parse_new_segment_full (event, &update, &rate, &applied_rate,
&format, &start, &stop, &pos);
+
GST_DEBUG_OBJECT (mpegvideoparse,
- "Pushing newseg rate %g, applied rate %g, "
- "format %d, start %lld, stop %lld, pos %lld\n",
+ "Pushing newseg rate %g, applied rate %g, format %d, start %"
+ G_GINT64_FORMAT ", stop %" G_GINT64_FORMAT ", pos %" G_GINT64_FORMAT,
rate, applied_rate, format, start, stop, pos);
res = gst_pad_event_default (pad, event);
@@ -570,7 +499,6 @@ mpv_parse_sink_event (GstPad * pad, GstEvent * event)
res = gst_pad_event_default (pad, event);
break;
case GST_EVENT_EOS:
-
/* Push any remaining buffers out, then flush. */
mpeg_packetiser_handle_eos (&mpegvideoparse->packer);
mpegvideoparse_drain_avail (mpegvideoparse);
generated by cgit v1.2.1 (git 2.18.0) at 2025-01-15 22:41:53 +0000