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-rw-r--r--gst/h264parse/gsth264parse.c127
-rw-r--r--gst/h264parse/gsth264parse.h1
2 files changed, 97 insertions, 31 deletions
diff --git a/gst/h264parse/gsth264parse.c b/gst/h264parse/gsth264parse.c
index 45d63379..91c75734 100644
--- a/gst/h264parse/gsth264parse.c
+++ b/gst/h264parse/gsth264parse.c
@@ -127,14 +127,14 @@ gst_nal_list_delete_head (GstNalList * list)
* emulation_prevention_three_bytes. */
typedef struct
{
- guint8 *data;
- guint8 *end;
+ const guint8 *data;
+ const guint8 *end;
gint head; /* bitpos in the cache of next bit */
guint64 cache; /* cached bytes */
} GstNalBs;
static void
-gst_nal_bs_init (GstNalBs * bs, guint8 * data, guint size)
+gst_nal_bs_init (GstNalBs * bs, const guint8 * data, guint size)
{
bs->data = data;
bs->end = data + size;
@@ -335,6 +335,8 @@ gst_h264_parse_sink_setcaps (GstPad * pad, GstCaps * caps)
GstH264Parse *h264parse;
GstStructure *str;
const GValue *value;
+ guint8 *data;
+ guint size;
h264parse = GST_H264PARSE (GST_PAD_PARENT (pad));
@@ -342,18 +344,59 @@ gst_h264_parse_sink_setcaps (GstPad * pad, GstCaps * caps)
/* packetized video has a codec_data */
if ((value = gst_structure_get_value (str, "codec_data"))) {
+ GstBuffer *buffer;
+ gint profile;
+
GST_DEBUG_OBJECT (h264parse, "have packetized h264");
h264parse->packetized = TRUE;
+
+ buffer = gst_value_get_buffer (value);
+ data = GST_BUFFER_DATA (buffer);
+ size = GST_BUFFER_SIZE (buffer);
+
+ /* parse the avcC data */
+ if (size < 7)
+ goto avcc_too_small;
+ /* parse the version, this must be 1 */
+ if (data[0] != 1)
+ goto wrong_version;
+
+ /* AVCProfileIndication */
+ /* profile_compat */
+ /* AVCLevelIndication */
+ profile = (data[1] << 16) | (data[2] << 8) | data[3];
+ GST_DEBUG_OBJECT (h264parse, "profile %06x", profile);
+
+ /* 6 bits reserved | 2 bits lengthSizeMinusOne */
+ /* this is the number of bytes in front of the NAL units to mark their
+ * length */
+ h264parse->nal_length_size = (data[4] & 0x03) + 1;
+ GST_DEBUG_OBJECT (h264parse, "nal length %u", h264parse->nal_length_size);
+
/* FIXME, PPS, SPS have vital info for detecting new I-frames */
} else {
GST_DEBUG_OBJECT (h264parse, "have bytestream h264");
h264parse->packetized = FALSE;
+ /* we have 4 sync bytes */
+ h264parse->nal_length_size = 4;
}
/* forward the caps */
res = gst_pad_set_caps (h264parse->srcpad, caps);
return res;
+
+ /* ERRORS */
+avcc_too_small:
+ {
+ GST_ERROR_OBJECT (h264parse, "avcC size %u < 7", size);
+ return FALSE;
+ }
+wrong_version:
+ {
+ GST_ERROR_OBJECT (h264parse, "wrong avcC version");
+ return FALSE;
+ }
}
static void
@@ -382,31 +425,30 @@ gst_h264_parse_chain_forward (GstH264Parse * h264parse, gboolean discont,
{
GstFlowReturn res = GST_FLOW_OK;
const guint8 *data;
+ GstClockTime timestamp;
if (discont) {
gst_adapter_clear (h264parse->adapter);
h264parse->discont = TRUE;
}
+ timestamp = GST_BUFFER_TIMESTAMP (buffer);
+
gst_adapter_push (h264parse->adapter, buffer);
while (res == GST_FLOW_OK) {
gint i;
gint next_nalu_pos = -1;
- guint32 nalu_size;
gint avail;
gboolean delta_unit = TRUE;
avail = gst_adapter_available (h264parse->adapter);
- if (avail < 5)
+ if (avail < h264parse->nal_length_size + 1)
break;
data = gst_adapter_peek (h264parse->adapter, avail);
- nalu_size = (data[0] << 24)
- + (data[1] << 16) + (data[2] << 8) + data[3];
-
- if (nalu_size == 1) {
- /* Bytestream format */
+ if (!h264parse->packetized) {
+ /* Bytestream format, first 4 bytes are sync code */
/* Find next NALU header */
for (i = 1; i < avail - 4; ++i) {
if (data[i + 0] == 0 && data[i + 1] == 0 && data[i + 2] == 0
@@ -416,21 +458,32 @@ gst_h264_parse_chain_forward (GstH264Parse * h264parse, gboolean discont,
}
}
} else {
+ guint32 nalu_size;
+
+ nalu_size = 0;
+ for (i = 0; i < h264parse->nal_length_size; i++)
+ nalu_size = (nalu_size << 8) | data[i];
+
/* Packetized format, see if we have to split it, usually splitting is not
* a good idea as decoders have no way of handling it. */
if (h264parse->split_packetized) {
- if (nalu_size + 4 <= avail)
- next_nalu_pos = nalu_size + 4;
+ if (nalu_size + h264parse->nal_length_size <= avail)
+ next_nalu_pos = nalu_size + h264parse->nal_length_size;
} else {
next_nalu_pos = avail;
}
}
+
+ /* skip nalu_size bytes or sync */
+ data += h264parse->nal_length_size;
+ avail -= h264parse->nal_length_size;
+
/* Figure out if this is a delta unit */
{
gint nal_type, nal_ref_idc;
- nal_type = (data[4] & 0x1f);
- nal_ref_idc = (data[4] & 0x60) >> 5;
+ nal_type = (data[0] & 0x1f);
+ nal_ref_idc = (data[0] & 0x60) >> 5;
GST_DEBUG_OBJECT (h264parse, "NAL type: %d, ref_idc: %d", nal_type,
nal_ref_idc);
@@ -439,9 +492,8 @@ gst_h264_parse_chain_forward (GstH264Parse * h264parse, gboolean discont,
if (nal_type >= NAL_SLICE && nal_type <= NAL_SLICE_IDR) {
GstNalBs bs;
gint first_mb_in_slice, slice_type;
- guint8 *bs_data = (guint8 *) data + 5;
- gst_nal_bs_init (&bs, bs_data, avail - 5);
+ gst_nal_bs_init (&bs, data + 1, avail - 1);
first_mb_in_slice = gst_nal_bs_read_ue (&bs);
slice_type = gst_nal_bs_read_ue (&bs);
@@ -495,12 +547,13 @@ gst_h264_parse_chain_forward (GstH264Parse * h264parse, gboolean discont,
h264parse->discont = FALSE;
}
- if (delta_unit) {
+ if (delta_unit)
GST_BUFFER_FLAG_SET (outbuf, GST_BUFFER_FLAG_DELTA_UNIT);
- }
+ else
+ GST_BUFFER_FLAG_UNSET (outbuf, GST_BUFFER_FLAG_DELTA_UNIT);
gst_buffer_set_caps (outbuf, GST_PAD_CAPS (h264parse->srcpad));
- GST_BUFFER_TIMESTAMP (outbuf) = GST_BUFFER_TIMESTAMP (buffer);
+ GST_BUFFER_TIMESTAMP (outbuf) = timestamp;
res = gst_pad_push (h264parse->srcpad, outbuf);
} else {
/* NALU can not be parsed yet, we wait for more data in the adapter. */
@@ -584,19 +637,29 @@ gst_h264_parse_queue_buffer (GstH264Parse * parse, GstBuffer * buffer)
/* now parse all the NAL units in this buffer, for bytestream we only have one
* NAL unit but for packetized streams we can have multiple ones */
- while (size >= 5) {
- nalu_size = (data[0] << 24)
- + (data[1] << 16) + (data[2] << 8) + data[3];
+ while (size >= parse->nal_length_size + 1) {
+ gint i;
+
+ nalu_size = 0;
+ if (parse->packetized) {
+ for (i = 0; i < parse->nal_length_size; i++)
+ nalu_size = (nalu_size << 8) | data[i];
+ }
+
+ /* skip nalu_size or sync bytes */
+ data += parse->nal_length_size;
+ size -= parse->nal_length_size;
- link->nal_ref_idc = (data[4] & 0x60) >> 5;
- link->nal_type = (data[4] & 0x1f);
+ link->nal_ref_idc = (data[0] & 0x60) >> 5;
+ link->nal_type = (data[0] & 0x1f);
+ /* nalu_size is 0 for bytestream, we have a complete packet */
GST_DEBUG_OBJECT (parse, "size: %u, NAL type: %d, ref_idc: %d",
nalu_size, link->nal_type, link->nal_ref_idc);
/* first parse some things needed to get to the frame type */
if (link->nal_type >= NAL_SLICE && link->nal_type <= NAL_SLICE_IDR) {
- gst_nal_bs_init (&bs, data + 5, size - 5);
+ gst_nal_bs_init (&bs, data + 1, size - 1);
link->first_mb_in_slice = gst_nal_bs_read_ue (&bs);
link->slice_type = gst_nal_bs_read_ue (&bs);
@@ -629,11 +692,11 @@ gst_h264_parse_queue_buffer (GstH264Parse * parse, GstBuffer * buffer)
}
}
/* bytestream, we can exit now */
- if (nalu_size == 1)
+ if (!parse->packetized)
break;
- /* packetized format, continue parsing all packets, skip size */
- nalu_size += 4;
+ /* packetized format, continue parsing all packets, skip size, we already
+ * skipped the nal_length_size bytes */
data += nalu_size;
size -= nalu_size;
}
@@ -717,6 +780,7 @@ gst_h264_parse_chain_reverse (GstH264Parse * h264parse, gboolean discont,
* store them */
GST_DEBUG_OBJECT (h264parse, "copied packetized buffer");
res = gst_h264_parse_queue_buffer (h264parse, gbuf);
+ gbuf = NULL;
} else {
/* bytestream, we have to split the NALUs on the sync markers */
code = 0xffffffff;
@@ -808,10 +872,11 @@ gst_h264_parse_chain (GstPad * pad, GstBuffer * buffer)
if (!gst_pad_set_caps (h264parse->srcpad, caps))
goto caps_failed;
- /* we assume the bytestream format but won't really fail otherwise if the
- * data turns out to be a nicely aligned packetized format (except we don't
- * do the codec_data caps with the PPS and SPS). */
+ /* we assume the bytestream format. If the data turns out to be packetized,
+ * we have a problem because we don't know the length of the nalu_size
+ * indicator. Packetized input MUST set the codec_data. */
h264parse->packetized = FALSE;
+ h264parse->nal_length_size = 4;
gst_caps_unref (caps);
}
diff --git a/gst/h264parse/gsth264parse.h b/gst/h264parse/gsth264parse.h
index 4dc74228..2bae3f8c 100644
--- a/gst/h264parse/gsth264parse.h
+++ b/gst/h264parse/gsth264parse.h
@@ -52,6 +52,7 @@ struct _GstH264Parse
GstPad *srcpad;
gboolean split_packetized;
+ guint nal_length_size;
GstSegment segment;
gboolean packetized;
generated by cgit v1.2.1 (git 2.18.0) at 2024-09-19 06:29:07 +0000