rtph264depay: optionally merge NALUs into Access Units

... which may be expected/desired by some downstream decoders
(and spec-wise highly recommended for at least non-bytestream mode).
This commit is contained in:
Mark Nauwelaerts 2009-11-26 16:14:30 +01:00
parent baa28ddedf
commit e49e71a1d9
2 changed files with 125 additions and 15 deletions

View file

@ -31,11 +31,13 @@ GST_DEBUG_CATEGORY_STATIC (rtph264depay_debug);
#define GST_CAT_DEFAULT (rtph264depay_debug)
#define DEFAULT_BYTE_STREAM TRUE
#define DEFAULT_ACCESS_UNIT FALSE
enum
{
PROP_0,
PROP_BYTE_STREAM,
PROP_ACCESS_UNIT,
PROP_LAST
};
@ -134,6 +136,10 @@ gst_rtp_h264_depay_class_init (GstRtpH264DepayClass * klass)
g_param_spec_boolean ("byte-stream", "Byte Stream",
"Generate byte stream format of NALU", DEFAULT_BYTE_STREAM,
G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
g_object_class_install_property (G_OBJECT_CLASS (klass), PROP_ACCESS_UNIT,
g_param_spec_boolean ("access-unit", "Access Unit",
"Merge NALU into AU (picture)", DEFAULT_ACCESS_UNIT,
G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
gstelement_class->change_state = gst_rtp_h264_depay_change_state;
@ -149,7 +155,9 @@ gst_rtp_h264_depay_init (GstRtpH264Depay * rtph264depay,
GstRtpH264DepayClass * klass)
{
rtph264depay->adapter = gst_adapter_new ();
rtph264depay->picture_adapter = gst_adapter_new ();
rtph264depay->byte_stream = DEFAULT_BYTE_STREAM;
rtph264depay->merge = DEFAULT_ACCESS_UNIT;
}
static void
@ -163,6 +171,7 @@ gst_rtp_h264_depay_finalize (GObject * object)
gst_buffer_unref (rtph264depay->codec_data);
g_object_unref (rtph264depay->adapter);
g_object_unref (rtph264depay->picture_adapter);
G_OBJECT_CLASS (parent_class)->finalize (object);
}
@ -179,6 +188,9 @@ gst_rtp_h264_depay_set_property (GObject * object, guint prop_id,
case PROP_BYTE_STREAM:
rtph264depay->byte_stream = g_value_get_boolean (value);
break;
case PROP_ACCESS_UNIT:
rtph264depay->merge = g_value_get_boolean (value);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
break;
@ -197,6 +209,9 @@ gst_rtp_h264_depay_get_property (GObject * object, guint prop_id,
case PROP_BYTE_STREAM:
g_value_set_boolean (value, rtph264depay->byte_stream);
break;
case PROP_ACCESS_UNIT:
g_value_set_boolean (value, rtph264depay->merge);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
break;
@ -374,8 +389,68 @@ incomplete_caps:
}
}
/* FIXME, non-bytestream handling is freaking out ffmpeg. Apparently we need to
* group all NAL units belonging to one frame together */
static GstBuffer *
gst_rtp_h264_depay_push_nal (GstRtpH264Depay * rtph264depay, GstBuffer * nal,
GstClockTime timestamp)
{
gint nal_type;
guint8 *data;
GstBuffer *outbuf = NULL;
guint outsize;
gboolean start = FALSE;
data = GST_BUFFER_DATA (nal);
/* caller ensures number of bytes available */
nal_type = data[4] & 0x1f;
GST_DEBUG_OBJECT (rtph264depay, "collecting NALU type %d", nal_type);
/* consider a coded slices (IDR or not) to start a picture,
* (so ending the previous one) if first_mb_in_slice == 0
* (non-0 is part of previous one) */
/* NOTE this is not entirely according to Access Unit specs in 7.4.1.2.4,
* but in practice it works in sane cases, needs not much parsing,
* and also works with broken frame_num in NAL (where spec-wise would fail) */
if (nal_type == 1 || nal_type == 2 || nal_type == 5) {
if (rtph264depay->picture_start) {
if (data[5] & 0x80) {
/* first_mb_in_slice == 0 */
rtph264depay->picture_complete = TRUE;
start = TRUE;
}
/* otherwise simply collect */
} else {
rtph264depay->picture_start = TRUE;
}
} else if (nal_type >= 6 && nal_type <= 9) {
/* SEI, SPS, PPS, AU terminate picture */
if (rtph264depay->picture_start)
rtph264depay->picture_complete = TRUE;
/* otherwise simply collect */
}
if (rtph264depay->picture_complete) {
outsize = gst_adapter_available (rtph264depay->picture_adapter);
outbuf = gst_adapter_take_buffer (rtph264depay->picture_adapter, outsize);
rtph264depay->picture_complete = FALSE;
rtph264depay->picture_start = start;
if (G_UNLIKELY (rtph264depay->codec_data)) {
outbuf = gst_buffer_join (rtph264depay->codec_data, outbuf);
rtph264depay->codec_data = NULL;
}
GST_BUFFER_TIMESTAMP (outbuf) = rtph264depay->last_ts;
if (GST_CLOCK_TIME_IS_VALID (timestamp) &&
GST_CLOCK_TIME_IS_VALID (rtph264depay->last_ts))
GST_BUFFER_DURATION (outbuf) = timestamp - rtph264depay->last_ts;
}
rtph264depay->last_ts = timestamp;
gst_adapter_push (rtph264depay->picture_adapter, nal);
return outbuf;
}
static GstBuffer *
gst_rtp_h264_depay_process (GstBaseRTPDepayload * depayload, GstBuffer * buf)
{
@ -398,6 +473,11 @@ gst_rtp_h264_depay_process (GstBaseRTPDepayload * depayload, GstBuffer * buf)
guint8 nal_ref_idc;
guint8 *outdata;
guint outsize, nalu_size;
GstClockTime ts;
/* baseclass already did this, would be nice not to have to redo ... */
ts = GST_BUFFER_TIMESTAMP (buf);
ts = gst_segment_to_running_time (&depayload->segment, GST_FORMAT_TIME, ts);
payload_len = gst_rtp_buffer_get_payload_len (buf);
payload = gst_rtp_buffer_get_payload (buf);
@ -441,7 +521,7 @@ gst_rtp_h264_depay_process (GstBaseRTPDepayload * depayload, GstBuffer * buf)
rtph264depay->wait_start = FALSE;
/* prepend codec_data */
if (rtph264depay->codec_data) {
if (!rtph264depay->merge && rtph264depay->codec_data) {
gst_adapter_push (rtph264depay->adapter, rtph264depay->codec_data);
rtph264depay->codec_data = NULL;
}
@ -477,18 +557,26 @@ gst_rtp_h264_depay_process (GstBaseRTPDepayload * depayload, GstBuffer * buf)
outdata += sizeof (sync_bytes);
memcpy (outdata, payload, nalu_size);
gst_adapter_push (rtph264depay->adapter, outbuf);
if (!rtph264depay->merge)
gst_adapter_push (rtph264depay->adapter, outbuf);
else {
outbuf = gst_rtp_h264_depay_push_nal (rtph264depay, outbuf, ts);
if (outbuf) {
gst_buffer_set_caps (outbuf, GST_PAD_CAPS (depayload->srcpad));
gst_base_rtp_depayload_push_ts (depayload, ts, outbuf);
}
}
payload += nalu_size;
payload_len -= nalu_size;
}
outsize = gst_adapter_available (rtph264depay->adapter);
outbuf = gst_adapter_take_buffer (rtph264depay->adapter, outsize);
gst_buffer_set_caps (outbuf, GST_PAD_CAPS (depayload->srcpad));
return outbuf;
if (!rtph264depay->merge) {
outsize = gst_adapter_available (rtph264depay->adapter);
outbuf = gst_adapter_take_buffer (rtph264depay->adapter, outsize);
gst_buffer_set_caps (outbuf, GST_PAD_CAPS (depayload->srcpad));
return outbuf;
}
}
case 26:
/* MTAP16 Multi-time aggregation packet 5.7.2 */
@ -581,15 +669,22 @@ gst_rtp_h264_depay_process (GstBaseRTPDepayload * depayload, GstBuffer * buf)
outdata[2] = (outsize >> 8);
outdata[3] = (outsize);
}
gst_buffer_set_caps (outbuf, GST_PAD_CAPS (depayload->srcpad));
/* push codec_data first */
if (rtph264depay->codec_data) {
if (!rtph264depay->merge && rtph264depay->codec_data) {
gst_buffer_set_caps (rtph264depay->codec_data,
GST_PAD_CAPS (depayload->srcpad));
gst_base_rtp_depayload_push (depayload, rtph264depay->codec_data);
rtph264depay->codec_data = NULL;
}
if (rtph264depay->merge) {
outbuf = gst_rtp_h264_depay_push_nal (rtph264depay, outbuf, ts);
if (!outbuf)
break;
}
gst_buffer_set_caps (outbuf, GST_PAD_CAPS (depayload->srcpad));
return outbuf;
}
break;
@ -614,15 +709,21 @@ gst_rtp_h264_depay_process (GstBaseRTPDepayload * depayload, GstBuffer * buf)
outdata += sizeof (sync_bytes);
memcpy (outdata, payload, nalu_size);
gst_buffer_set_caps (outbuf, GST_PAD_CAPS (depayload->srcpad));
/* push codec_data first */
if (rtph264depay->codec_data) {
if (!rtph264depay->merge && rtph264depay->codec_data) {
gst_buffer_set_caps (rtph264depay->codec_data,
GST_PAD_CAPS (depayload->srcpad));
gst_base_rtp_depayload_push (depayload, rtph264depay->codec_data);
rtph264depay->codec_data = NULL;
}
if (rtph264depay->merge) {
outbuf = gst_rtp_h264_depay_push_nal (rtph264depay, outbuf, ts);
if (!outbuf)
break;
}
gst_buffer_set_caps (outbuf, GST_PAD_CAPS (depayload->srcpad));
return outbuf;
}
}
@ -665,6 +766,9 @@ gst_rtp_h264_depay_change_state (GstElement * element,
case GST_STATE_CHANGE_READY_TO_PAUSED:
gst_adapter_clear (rtph264depay->adapter);
rtph264depay->wait_start = TRUE;
gst_adapter_clear (rtph264depay->picture_adapter);
rtph264depay->picture_start = FALSE;
rtph264depay->picture_complete = FALSE;
break;
default:
break;

View file

@ -50,6 +50,12 @@ struct _GstRtpH264Depay
GstAdapter *adapter;
gboolean wait_start;
/* nal merging */
gboolean merge;
GstAdapter *picture_adapter;
gboolean picture_start;
gboolean picture_complete;
GstClockTime last_ts;
};
struct _GstRtpH264DepayClass