h264parse: remove _chain hack

As we can now rely upon being passed upstream delineated data in
::handle_frame(), the latter can also parse avc formatted data
without having to intercept baseparse's chain function.

While this evidently requires 2 separate parsing paths, each can
be streamlined accordingly.
This commit is contained in:
Mark Nauwelaerts 2012-02-15 16:38:32 +01:00
parent b8a78c6b37
commit c7216162e4
2 changed files with 109 additions and 135 deletions

View file

@ -94,8 +94,6 @@ static void gst_h264_parse_get_property (GObject * object, guint prop_id,
static gboolean gst_h264_parse_set_caps (GstBaseParse * parse, GstCaps * caps);
static GstCaps *gst_h264_parse_get_caps (GstBaseParse * parse,
GstCaps * filter);
static GstFlowReturn gst_h264_parse_chain (GstPad * pad, GstObject * parent,
GstBuffer * buffer);
static gboolean gst_h264_parse_event (GstBaseParse * parse, GstEvent * event);
static gboolean gst_h264_parse_src_event (GstBaseParse * parse,
GstEvent * event);
@ -147,14 +145,6 @@ static void
gst_h264_parse_init (GstH264Parse * h264parse)
{
h264parse->frame_out = gst_adapter_new ();
/* retrieve and intercept baseparse.
* Quite HACKish, but fairly OK since it is needed to perform avc packet
* splitting, which is the penultimate de-parsing */
h264parse->parse_chain =
GST_PAD_CHAINFUNC (GST_BASE_PARSE_SINK_PAD (h264parse));
gst_pad_set_chain_function (GST_BASE_PARSE_SINK_PAD (h264parse),
gst_h264_parse_chain);
}
@ -200,6 +190,7 @@ gst_h264_parse_reset (GstH264Parse * h264parse)
gst_buffer_replace (&h264parse->codec_data, NULL);
h264parse->nal_length_size = 4;
h264parse->packetized = FALSE;
h264parse->transform = FALSE;
h264parse->align = GST_H264_PARSE_ALIGN_NONE;
h264parse->format = GST_H264_PARSE_FORMAT_NONE;
@ -322,7 +313,8 @@ gst_h264_parse_format_from_caps (GstCaps * caps, guint * format, guint * align)
/* check downstream caps to configure format and alignment */
static void
gst_h264_parse_negotiate (GstH264Parse * h264parse, GstCaps * in_caps)
gst_h264_parse_negotiate (GstH264Parse * h264parse, gint in_format,
GstCaps * in_caps)
{
GstCaps *caps;
guint format = GST_H264_PARSE_FORMAT_NONE;
@ -370,6 +362,8 @@ gst_h264_parse_negotiate (GstH264Parse * h264parse, GstCaps * in_caps)
h264parse->format = format;
h264parse->align = align;
h264parse->transform = (in_format != h264parse->format);
}
static GstBuffer *
@ -517,7 +511,7 @@ gst_h264_parse_process_nal (GstH264Parse * h264parse, GstH264NalUnit * nalu)
}
/* mark SEI pos */
if (h264parse->sei_pos == -1) {
if (h264parse->format == GST_H264_PARSE_FORMAT_AVC)
if (h264parse->transform)
h264parse->sei_pos = gst_adapter_available (h264parse->frame_out);
else
h264parse->sei_pos = nalu->sc_offset;
@ -560,7 +554,7 @@ gst_h264_parse_process_nal (GstH264Parse * h264parse, GstH264NalUnit * nalu)
/* mark where config needs to go if interval expired */
/* mind replacement buffer if applicable */
if (h264parse->idr_pos == -1) {
if (h264parse->format == GST_H264_PARSE_FORMAT_AVC)
if (h264parse->transform)
h264parse->idr_pos = gst_adapter_available (h264parse->frame_out);
else
h264parse->idr_pos = nalu->sc_offset;
@ -580,7 +574,7 @@ gst_h264_parse_process_nal (GstH264Parse * h264parse, GstH264NalUnit * nalu)
/* if AVC output needed, collect properly prefixed nal in adapter,
* and use that to replace outgoing buffer data later on */
if (h264parse->format == GST_H264_PARSE_FORMAT_AVC) {
if (h264parse->transform) {
GstBuffer *buf;
GST_LOG_OBJECT (h264parse, "collecting NAL in AVC frame");
@ -639,6 +633,93 @@ gst_h264_parse_collect_nal (GstH264Parse * h264parse, const guint8 * data,
return complete;
}
static GstFlowReturn
gst_h264_parse_handle_frame_packetized (GstBaseParse * parse,
GstBaseParseFrame * frame)
{
GstH264Parse *h264parse = GST_H264_PARSE (parse);
GstBuffer *buffer = frame->buffer;
GstFlowReturn ret = GST_FLOW_OK;
GstH264ParserResult parse_res;
GstH264NalUnit nalu;
const guint nl = h264parse->nal_length_size;
GstMapInfo map;
gint left;
if (nl < 1 || nl > 4) {
GST_DEBUG_OBJECT (h264parse, "insufficient data to split input");
return GST_FLOW_NOT_NEGOTIATED;
}
/* need to save buffer from invalidation upon _finish_frame */
if (h264parse->split_packetized)
buffer = gst_buffer_copy (frame->buffer);
gst_buffer_map (buffer, &map, GST_MAP_READ);
left = map.size;
GST_LOG_OBJECT (h264parse,
"processing packet buffer of size %" G_GSIZE_FORMAT, map.size);
parse_res = gst_h264_parser_identify_nalu_avc (h264parse->nalparser,
map.data, 0, map.size, nl, &nalu);
while (parse_res == GST_H264_PARSER_OK) {
GST_DEBUG_OBJECT (h264parse, "AVC nal offset %d", nalu.offset + nalu.size);
/* either way, have a look at it */
gst_h264_parse_process_nal (h264parse, &nalu);
/* dispatch per NALU if needed */
if (h264parse->split_packetized) {
/* note we don't need to come up with a sub-buffer, since
* subsequent code only considers input buffer's metadata.
* Real data is either taken from input by baseclass or
* a replacement output buffer is provided anyway. */
gst_h264_parse_parse_frame (parse, frame);
ret = gst_base_parse_finish_frame (parse, frame, nl + nalu.size);
left -= nl + nalu.size;
}
parse_res = gst_h264_parser_identify_nalu_avc (h264parse->nalparser,
map.data, nalu.offset + nalu.size, map.size, nl, &nalu);
}
gst_buffer_unmap (buffer, &map);
if (!h264parse->split_packetized) {
gst_h264_parse_parse_frame (parse, frame);
ret = gst_base_parse_finish_frame (parse, frame, map.size);
} else {
gst_buffer_unref (buffer);
if (G_UNLIKELY (left)) {
/* should not be happening for nice AVC */
GST_WARNING_OBJECT (parse, "skipping leftover AVC data %d", left);
frame->flags |= GST_BASE_PARSE_FRAME_FLAG_DROP;
ret = gst_base_parse_finish_frame (parse, frame, map.size);
}
}
if (parse_res == GST_H264_PARSER_NO_NAL_END ||
parse_res == GST_H264_PARSER_BROKEN_DATA) {
if (h264parse->split_packetized) {
GST_ELEMENT_ERROR (h264parse, STREAM, FAILED, (NULL),
("invalid AVC input data"));
gst_buffer_unref (buffer);
return GST_FLOW_ERROR;
} else {
/* do not meddle to much in this case */
GST_DEBUG_OBJECT (h264parse, "parsing packet failed");
}
}
return ret;
}
static GstFlowReturn
gst_h264_parse_handle_frame (GstBaseParse * parse,
GstBaseParseFrame * frame, gint * skipsize)
@ -655,6 +736,10 @@ gst_h264_parse_handle_frame (GstBaseParse * parse,
GstH264ParserResult pres;
gint framesize;
/* delegate in packetized case, no skipping should be needed */
if (h264parse->packetized)
return gst_h264_parse_handle_frame_packetized (parse, frame);
gst_buffer_map (buffer, &map, GST_MAP_READ);
data = map.data;
size = map.size;
@ -668,7 +753,7 @@ gst_h264_parse_handle_frame (GstBaseParse * parse,
/* need to configure aggregation */
if (G_UNLIKELY (h264parse->format == GST_H264_PARSE_FORMAT_NONE))
gst_h264_parse_negotiate (h264parse, NULL);
gst_h264_parse_negotiate (h264parse, GST_H264_PARSE_FORMAT_BYTE, NULL);
/* avoid stale cached parsing state */
if (frame->flags & GST_BASE_PARSE_FRAME_FLAG_NEW_FRAME) {
@ -710,14 +795,9 @@ gst_h264_parse_handle_frame (GstBaseParse * parse,
}
while (TRUE) {
if (h264parse->packetized_chunked)
pres =
gst_h264_parser_identify_nalu_unchecked (nalparser, data, current_off,
size, &nalu);
else
pres =
gst_h264_parser_identify_nalu (nalparser, data, current_off, size,
&nalu);
pres =
gst_h264_parser_identify_nalu (nalparser, data, current_off, size,
&nalu);
switch (pres) {
case GST_H264_PARSER_OK:
@ -779,7 +859,7 @@ gst_h264_parse_handle_frame (GstBaseParse * parse,
/* simulate no next nal if none needed */
nonext = nonext || (h264parse->align == GST_H264_PARSE_ALIGN_NAL);
if (!nonext && !h264parse->packetized_chunked) {
if (!nonext) {
if (nalu.offset + nalu.size + 4 + 2 > size) {
GST_DEBUG_OBJECT (h264parse, "not enough data for next NALU");
if (drain) {
@ -796,16 +876,6 @@ gst_h264_parse_handle_frame (GstBaseParse * parse,
if (nonext)
break;
/* In packetized mode we know there's only on NALU in each input packet,
* but we may not have seen the whole AU already, possibly need more */
if (h264parse->packetized_chunked) {
if (h264parse->packetized_last)
break;
/* next NALU expected at end of current data */
current_off = size;
goto more;
}
/* if no next nal, we know it's complete here */
if (gst_h264_parse_collect_nal (h264parse, data, size, &nalu))
break;
@ -1689,7 +1759,7 @@ gst_h264_parse_set_caps (GstBaseParse * parse, GstCaps * caps)
"alignment", G_TYPE_STRING,
gst_h264_parse_get_string (h264parse, FALSE, align), NULL);
/* negotiate with downstream, sets ->format and ->align */
gst_h264_parse_negotiate (h264parse, in_caps);
gst_h264_parse_negotiate (h264parse, format, in_caps);
gst_caps_unref (in_caps);
}
@ -1705,7 +1775,8 @@ gst_h264_parse_set_caps (GstBaseParse * parse, GstCaps * caps)
h264parse->push_codec = TRUE;
h264parse->have_sps = FALSE;
h264parse->have_pps = FALSE;
h264parse->split_packetized = TRUE;
if (h264parse->align == GST_H264_PARSE_ALIGN_NAL)
h264parse->split_packetized = TRUE;
h264parse->packetized = TRUE;
}
@ -1874,100 +1945,6 @@ gst_h264_parse_src_event (GstBaseParse * parse, GstEvent * event)
return res;
}
static GstFlowReturn
gst_h264_parse_chain (GstPad * pad, GstObject * parent, GstBuffer * buffer)
{
GstH264Parse *h264parse = GST_H264_PARSE (parent);
if (h264parse->packetized && buffer) {
GstBuffer *sub;
GstFlowReturn ret = GST_FLOW_OK;
GstH264ParserResult parse_res;
GstH264NalUnit nalu;
const guint nl = h264parse->nal_length_size;
GstMapInfo map;
if (nl < 1 || nl > 4) {
GST_DEBUG_OBJECT (h264parse, "insufficient data to split input");
gst_buffer_unref (buffer);
return GST_FLOW_NOT_NEGOTIATED;
}
gst_buffer_map (buffer, &map, GST_MAP_READ);
GST_LOG_OBJECT (h264parse,
"processing packet buffer of size %" G_GSIZE_FORMAT, map.size);
parse_res = gst_h264_parser_identify_nalu_avc (h264parse->nalparser,
map.data, 0, map.size, nl, &nalu);
while (parse_res == GST_H264_PARSER_OK) {
GST_DEBUG_OBJECT (h264parse, "AVC nal offset %d",
nalu.offset + nalu.size);
if (h264parse->split_packetized) {
/* convert to NAL aligned byte stream input */
sub = gst_h264_parse_wrap_nal (h264parse, GST_H264_PARSE_FORMAT_BYTE,
nalu.data + nalu.offset, nalu.size);
/* at least this should make sense */
GST_BUFFER_TIMESTAMP (sub) = GST_BUFFER_TIMESTAMP (buffer);
/* transfer flags (e.g. DISCONT) for first fragment */
if (nalu.offset <= nl)
gst_buffer_copy_into (sub, buffer, GST_BUFFER_COPY_FLAGS, 0, -1);
/* in reverse playback, baseparse gathers buffers, so we cannot
* guarantee a buffer to contain a single whole NALU */
h264parse->packetized_chunked =
(GST_BASE_PARSE (h264parse)->segment.rate > 0.0);
h264parse->packetized_last =
(nalu.offset + nalu.size + nl >= gst_buffer_get_size (buffer));
GST_LOG_OBJECT (h264parse, "pushing NAL of size %d, last = %d",
nalu.size, h264parse->packetized_last);
ret = h264parse->parse_chain (pad, parent, sub);
} else {
/* pass-through: no looking for frames (and nal processing),
* so need to parse to collect data here */
/* NOTE: so if it is really configured to do so,
* pre_push can/will still insert codec-data at intervals,
* which is not really pure pass-through, but anyway ... */
gst_h264_parse_process_nal (h264parse, &nalu);
}
parse_res = gst_h264_parser_identify_nalu_avc (h264parse->nalparser,
map.data, nalu.offset + nalu.size, map.size, nl, &nalu);
}
gst_buffer_unmap (buffer, &map);
if (h264parse->split_packetized) {
gst_buffer_unref (buffer);
return ret;
} else {
/* nal processing in pass-through might have collected stuff;
* ensure nothing happens with this later on */
gst_adapter_clear (h264parse->frame_out);
}
if (parse_res == GST_H264_PARSER_NO_NAL_END ||
parse_res == GST_H264_PARSER_BROKEN_DATA) {
if (h264parse->split_packetized) {
GST_ELEMENT_ERROR (h264parse, STREAM, FAILED, (NULL),
("invalid AVC input data"));
gst_buffer_unref (buffer);
return GST_FLOW_ERROR;
} else {
/* do not meddle to much in this case */
GST_DEBUG_OBJECT (h264parse, "parsing packet failed");
}
}
}
return h264parse->parse_chain (pad, parent, buffer);
}
static void
gst_h264_parse_set_property (GObject * object, guint prop_id,
const GValue * value, GParamSpec * pspec)

View file

@ -53,8 +53,6 @@ struct _GstH264Parse
{
GstBaseParse baseparse;
GstPadChainFunction parse_chain;
/* stream */
gint width, height;
gint fps_num, fps_den;
@ -64,14 +62,14 @@ struct _GstH264Parse
GstBuffer *codec_data;
guint nal_length_size;
gboolean packetized;
gboolean split_packetized;
gboolean transform;
/* state */
GstH264NalParser *nalparser;
guint align;
guint format;
gint current_off;
gboolean packetized_last;
gboolean packetized_chunked;
GstClockTime last_report;
gboolean push_codec;
@ -107,7 +105,6 @@ struct _GstH264Parse
gboolean picture_start;
/* props */
gboolean split_packetized;
guint interval;
GstClockTime pending_key_unit_ts;