static GstFlowReturn
gst_h264_parse_parse_frame (GstBaseParse * parse, GstBaseParseFrame * frame)
{
GstH264Parse *h264parse;
GstBuffer *buffer;
guint av;
h264parse = GST_H264_PARSE (parse);
buffer = frame->buffer;
gst_h264_parse_update_src_caps (h264parse);
gst_h264_params_get_timestamp (h264parse->params,
&GST_BUFFER_TIMESTAMP (buffer), &GST_BUFFER_DURATION (buffer),
h264parse->frame_start);
if (h264parse->keyframe)
GST_BUFFER_FLAG_UNSET (buffer, GST_BUFFER_FLAG_DELTA_UNIT);
else
GST_BUFFER_FLAG_SET (buffer, GST_BUFFER_FLAG_DELTA_UNIT);
/* replace with transformed AVC output if applicable */
av = gst_adapter_available (h264parse->frame_out);
if (av) {
GstBuffer *buf;
buf = gst_adapter_take_buffer (h264parse->frame_out, av);
gst_buffer_copy_metadata (buf, buffer, GST_BUFFER_COPY_ALL);
gst_buffer_replace (&frame->buffer, buf);
}
return GST_FLOW_OK;
}
static void
gst_h264_parse_finalize (GObject * object)
{
GstH264Parse *h264parse = GST_H264_PARSE (object);
g_object_unref (h264parse->frame_out);
G_OBJECT_CLASS (parent_class)->finalize (object);
}
static gboolean
gst_h264_parse_stop (GstBaseParse * parse)
{
GstH264Parse *h264parse = GST_H264_PARSE (parse);
GST_DEBUG ("Stop");
gst_h264_parse_reset (h264parse);
gst_h264_params_free (h264parse->params);
h264parse->params = NULL;
return TRUE;
}
static gboolean
gst_h264_parse_start (GstBaseParse * parse)
{
GstH264Parse *h264parse = GST_H264_PARSE (parse);
GST_DEBUG ("Start");
gst_h264_parse_reset (h264parse);
gst_h264_params_create (&h264parse->params, GST_ELEMENT (h264parse));
gst_base_parse_set_min_frame_size (parse, 512);
return TRUE;
}
static void
gst_h264_parse_get_property (GObject * object, guint prop_id, GValue * value,
GParamSpec * pspec)
{
GstH264Parse *parse;
parse = GST_H264_PARSE (object);
switch (prop_id) {
case PROP_CONFIG_INTERVAL:
g_value_set_uint (value, parse->interval);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
break;
}
}
static void
gst_h264_parse_set_property (GObject * object, guint prop_id,
const GValue * value, GParamSpec * pspec)
{
GstH264Parse *parse;
parse = GST_H264_PARSE (object);
switch (prop_id) {
case PROP_SPLIT_PACKETIZED:
parse->split_packetized = g_value_get_boolean (value);
break;
case PROP_CONFIG_INTERVAL:
parse->interval = g_value_get_uint (value);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
break;
}
}
static gboolean
gst_h264_parse_set_caps (GstBaseParse * parse, GstCaps * caps)
{
GstH264Parse *h264parse;
GstStructure *str;
const GValue *value;
GstBuffer *buffer = NULL;
guint size;
h264parse = GST_H264_PARSE (parse);
/* reset */
h264parse->push_codec = FALSE;
str = gst_caps_get_structure (caps, 0);
/* accept upstream info if provided */
gst_structure_get_int (str, "width", &h264parse->width);
gst_structure_get_int (str, "height", &h264parse->height);
gst_structure_get_fraction (str, "framerate", &h264parse->fps_num,
&h264parse->fps_den);
/* packetized video has a codec_data */
if ((value = gst_structure_get_value (str, "codec_data"))) {
guint8 *data;
guint num_sps, num_pps, profile, len;
gint i;
GST_DEBUG_OBJECT (h264parse, "have packetized h264");
/* make note for optional split processing */
h264parse->packetized = TRUE;
buffer = gst_value_get_buffer (value);
if (!buffer)
goto wrong_type;
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);
num_sps = data[5] & 0x1f;
data += 6;
size -= 6;
for (i = 0; i < num_sps; i++) {
len = GST_READ_UINT16_BE (data);
if (size < len + 2 || len < 2)
goto avcc_too_small;
/* digest for later reference */
gst_h264_parse_process_nal (h264parse, data, 0, 2, len);
data += len + 2;
size -= len + 2;
}
num_pps = data[0];
data++;
size++;
for (i = 0; i < num_pps; i++) {
len = GST_READ_UINT16_BE (data);
if (size < len + 2 || len < 2)
goto avcc_too_small;
/* digest for later reference */
gst_h264_parse_process_nal (h264parse, data, 0, 2, len);
data += len + 2;
size -= len + 2;
}
} else {
GST_DEBUG_OBJECT (h264parse, "have bytestream h264");
/* nothing to pre-process */
h264parse->packetized = FALSE;
/* we have 4 sync bytes */
h264parse->nal_length_size = 4;
}
if (h264parse->packetized) {
if (h264parse->split_packetized) {
GST_DEBUG_OBJECT (h264parse,
"converting AVC to nal bytestream prior to parsing");
/* negotiate behaviour with upstream */
gst_h264_parse_negotiate (h264parse);
if (h264parse->format == GST_H264_PARSE_FORMAT_BYTE) {
/* arrange to insert codec-data in-stream if needed */
h264parse->push_codec = h264parse->packetized;
}
} else {
GST_DEBUG_OBJECT (h264parse, "passing on packetized AVC");
/* no choice to negotiate */
h264parse->format = GST_H264_PARSE_FORMAT_AVC;
h264parse->align = GST_H264_PARSE_ALIGN_AU;
/* fallback codec-data */
h264parse->codec_data = gst_buffer_ref (buffer);
/* pass through unharmed, though _chain will parse a bit */
gst_base_parse_set_format (parse,
GST_BASE_PARSE_FORMAT_PASSTHROUGH, TRUE);
/* we did parse codec-data and might supplement src caps */
gst_h264_parse_update_src_caps (h264parse);
}
}
/* src caps are only arranged for later on */
return TRUE;
/* ERRORS */
avcc_too_small:
{
GST_DEBUG_OBJECT (h264parse, "avcC size %u < 7", size);
goto refuse_caps;
}
wrong_version:
{
GST_DEBUG_OBJECT (h264parse, "wrong avcC version");
goto refuse_caps;
}
wrong_type:
{
GST_DEBUG_OBJECT (h264parse, "wrong codec-data type");
goto refuse_caps;
}
refuse_caps:
{
GST_WARNING_OBJECT (h264parse, "refused caps %" GST_PTR_FORMAT, caps);
return FALSE;
}
}
static GstFlowReturn
gst_h264_parse_pre_push_frame (GstBaseParse * parse, GstBaseParseFrame * frame)
{
GstH264Parse *h264parse;
GstBuffer *buffer;
h264parse = GST_H264_PARSE (parse);
buffer = frame->buffer;
/* periodic SPS/PPS sending */
if (h264parse->interval > 0 || h264parse->push_codec) {
GstClockTime timestamp = GST_BUFFER_TIMESTAMP (buffer);
guint64 diff;
/* init */
if (!GST_CLOCK_TIME_IS_VALID (h264parse->last_report)) {
h264parse->last_report = timestamp;
}
if (h264parse->idr_pos >= 0) {
GST_LOG_OBJECT (h264parse, "IDR nal at offset %d", h264parse->idr_pos);
if (timestamp > h264parse->last_report)
diff = timestamp - h264parse->last_report;
else
diff = 0;
GST_LOG_OBJECT (h264parse,
"now %" GST_TIME_FORMAT ", last SPS/PPS %" GST_TIME_FORMAT,
GST_TIME_ARGS (timestamp), GST_TIME_ARGS (h264parse->last_report));
GST_DEBUG_OBJECT (h264parse,
"interval since last SPS/PPS %" GST_TIME_FORMAT,
GST_TIME_ARGS (diff));
if (GST_TIME_AS_SECONDS (diff) >= h264parse->interval ||
h264parse->push_codec) {
GstBuffer *codec_nal;
gint i;
GstClockTime new_ts;
/* avoid overwriting a perfectly fine timestamp */
new_ts = GST_CLOCK_TIME_IS_VALID (timestamp) ? timestamp :
h264parse->last_report;
if (h264parse->align == GST_H264_PARSE_ALIGN_NAL) {
/* send separate config NAL buffers */
GST_DEBUG_OBJECT (h264parse, "- sending SPS/PPS");
for (i = 0; i < MAX_SPS_COUNT; i++) {
if ((codec_nal = h264parse->params->sps_nals[i])) {
GST_DEBUG_OBJECT (h264parse, "sending SPS nal");
gst_h264_parse_push_codec_buffer (h264parse, codec_nal,
timestamp);
h264parse->last_report = new_ts;
}
}
for (i = 0; i < MAX_PPS_COUNT; i++) {
if ((codec_nal = h264parse->params->pps_nals[i])) {
GST_DEBUG_OBJECT (h264parse, "sending PPS nal");
gst_h264_parse_push_codec_buffer (h264parse, codec_nal,
timestamp);
h264parse->last_report = new_ts;
}
}
} else {
/* insert config NALs into AU */
GstByteWriter bw;
GstBuffer *new_buf;
const gboolean bs = h264parse->format == GST_H264_PARSE_FORMAT_BYTE;
gst_byte_writer_init_with_size (&bw, GST_BUFFER_SIZE (buffer), FALSE);
gst_byte_writer_put_data (&bw, GST_BUFFER_DATA (buffer),
h264parse->idr_pos);
GST_DEBUG_OBJECT (h264parse, "- inserting SPS/PPS");
for (i = 0; i < MAX_SPS_COUNT; i++) {
if ((codec_nal = h264parse->params->sps_nals[i])) {
GST_DEBUG_OBJECT (h264parse, "inserting SPS nal");
gst_byte_writer_put_uint32_be (&bw,
bs ? 1 : GST_BUFFER_SIZE (codec_nal));
gst_byte_writer_put_data (&bw, GST_BUFFER_DATA (codec_nal),
GST_BUFFER_SIZE (codec_nal));
h264parse->last_report = new_ts;
}
}
for (i = 0; i < MAX_PPS_COUNT; i++) {
if ((codec_nal = h264parse->params->pps_nals[i])) {
GST_DEBUG_OBJECT (h264parse, "inserting PPS nal");
gst_byte_writer_put_uint32_be (&bw,
bs ? 1 : GST_BUFFER_SIZE (codec_nal));
gst_byte_writer_put_data (&bw, GST_BUFFER_DATA (codec_nal),
GST_BUFFER_SIZE (codec_nal));
h264parse->last_report = new_ts;
}
}
gst_byte_writer_put_data (&bw,
GST_BUFFER_DATA (buffer) + h264parse->idr_pos,
GST_BUFFER_SIZE (buffer) - h264parse->idr_pos);
/* collect result and push */
new_buf = gst_byte_writer_reset_and_get_buffer (&bw);
gst_buffer_copy_metadata (new_buf, buffer, GST_BUFFER_COPY_ALL);
gst_buffer_replace (&frame->buffer, new_buf);
}
}
/* we pushed whatever we had */
h264parse->push_codec = FALSE;
}
}
gst_h264_parse_reset_frame (h264parse);
return GST_FLOW_OK;
}
static gboolean
gst_h264_parse_check_valid_frame (GstBaseParse * parse,
GstBaseParseFrame * frame, guint * framesize, gint * skipsize)
{
GstH264Parse *h264parse = GST_H264_PARSE (parse);
GstBuffer *buffer = frame->buffer;
gint sc_pos, nal_pos, next_sc_pos, next_nal_pos;
guint8 *data;
guint size;
gboolean drain;
/* expect at least 3 bytes startcode == sc, and 2 bytes NALU payload */
if (G_UNLIKELY (GST_BUFFER_SIZE (buffer) < 5))
return FALSE;
/* need to configure aggregation */
if (G_UNLIKELY (h264parse->format == GST_H264_PARSE_FORMAT_NONE))
gst_h264_parse_negotiate (h264parse);
data = GST_BUFFER_DATA (buffer);
size = GST_BUFFER_SIZE (buffer);
GST_LOG_OBJECT (h264parse, "last_nal_pos: %d, last_scan_pos %d",
h264parse->last_nal_pos, h264parse->next_sc_pos);
nal_pos = h264parse->last_nal_pos;
next_sc_pos = h264parse->next_sc_pos;
if (!next_sc_pos) {
sc_pos = gst_h264_parse_find_sc (buffer, 0);
if (sc_pos == -1) {
/* SC not found, need more data */
sc_pos = GST_BUFFER_SIZE (buffer) - 3;
goto more;
}
nal_pos = sc_pos + 3;
next_sc_pos = nal_pos;
/* sc might have 2 or 3 0-bytes */
if (sc_pos > 0 && data[sc_pos - 1] == 00)
sc_pos--;
GST_LOG_OBJECT (h264parse, "found sc at offset %d", sc_pos);
} else {
/* previous checks already arrange sc at start */
sc_pos = 0;
}
drain = GST_BASE_PARSE_FRAME_DRAIN (frame);
while (TRUE) {
gint prev_sc_pos;
next_sc_pos = gst_h264_parse_find_sc (buffer, next_sc_pos);
if (next_sc_pos == -1) {
GST_LOG_OBJECT (h264parse, "no next sc");
if (drain) {
/* FLUSH/EOS, it's okay if we can't find the next frame */
next_sc_pos = size;
next_nal_pos = size;
} else {
next_sc_pos = size - 3;
goto more;
}
} else {
next_nal_pos = next_sc_pos + 3;
if (data[next_sc_pos - 1] == 00)
next_sc_pos--;
GST_LOG_OBJECT (h264parse, "found next sc at offset %d", next_sc_pos);
/* need at least 1 more byte of next NAL */
if (!drain && (next_nal_pos == size - 1))
goto more;
}
/* determine nal's sc position */
prev_sc_pos = nal_pos - 3;
g_assert (prev_sc_pos >= 0);
if (prev_sc_pos > 0 && data[prev_sc_pos - 1] == 0)
prev_sc_pos--;
/* already consume and gather info from NAL */
gst_h264_parse_process_nal (h264parse, data, prev_sc_pos, nal_pos,
next_sc_pos - nal_pos);
if (next_nal_pos >= size - 1 ||
gst_h264_parse_collect_nal (h264parse, data + nal_pos,
data + next_nal_pos))
break;
/* move along */
next_sc_pos = nal_pos = next_nal_pos;
}
*skipsize = sc_pos;
*framesize = next_sc_pos - sc_pos;
return TRUE;
more:
/* Ask for 1024 bytes more - this is an arbitrary choice */
gst_base_parse_set_min_frame_size (parse, GST_BUFFER_SIZE (buffer) + 1024);
/* skip up to initial startcode */
*skipsize = sc_pos;
/* resume scanning here next time */
h264parse->last_nal_pos = nal_pos;
h264parse->next_sc_pos = next_sc_pos;
return FALSE;
}
static GstFlowReturn
gst_h264_parse_chain (GstPad * pad, GstBuffer * buffer)
{
GstH264Parse *h264parse = GST_H264_PARSE (GST_PAD_PARENT (pad));
if (h264parse->packetized && buffer) {
GstByteReader br;
GstBuffer *sub;
GstFlowReturn ret = GST_FLOW_OK;
guint32 len;
const guint nl = h264parse->nal_length_size;
GST_LOG_OBJECT (h264parse, "processing packet buffer of size %d",
GST_BUFFER_SIZE (buffer));
gst_byte_reader_init_from_buffer (&br, buffer);
while (ret == GST_FLOW_OK && gst_byte_reader_get_remaining (&br)) {
GST_DEBUG_OBJECT (h264parse, "AVC nal offset %d",
gst_byte_reader_get_pos (&br));
if (gst_byte_reader_get_remaining (&br) < nl)
goto parse_failed;
switch (nl) {
case 4:
len = gst_byte_reader_get_uint32_be_unchecked (&br);
break;
case 3:
len = gst_byte_reader_get_uint24_be_unchecked (&br);
break;
case 2:
len = gst_byte_reader_get_uint16_be_unchecked (&br);
break;
case 1:
len = gst_byte_reader_get_uint8_unchecked (&br);
break;
default:
goto not_negotiated;
break;
}
GST_DEBUG_OBJECT (h264parse, "AVC nal size %d", len);
if (gst_byte_reader_get_remaining (&br) < len)
goto parse_failed;
if (h264parse->split_packetized) {
/* convert to NAL aligned byte stream input */
sub = gst_h264_parse_wrap_nal (h264parse, GST_H264_PARSE_FORMAT_BYTE,
(guint8 *) gst_byte_reader_get_data_unchecked (&br, len), len);
/* at least this should make sense */
GST_BUFFER_TIMESTAMP (sub) = GST_BUFFER_TIMESTAMP (buffer);
GST_LOG_OBJECT (h264parse, "pushing NAL of size %d", len);
ret = h264parse->parse_chain (pad, 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,
GST_BUFFER_DATA (buffer), gst_byte_reader_get_pos (&br) - nl,
gst_byte_reader_get_pos (&br), len);
gst_byte_reader_skip_unchecked (&br, len);
}
}
if (h264parse->split_packetized)
return ret;
}
exit:
/* nal processing in pass-through might have collected stuff;
* ensure nothing happens with this later on */
gst_adapter_clear (h264parse->frame_out);
return h264parse->parse_chain (pad, buffer);
/* ERRORS */
not_negotiated:
{
GST_DEBUG_OBJECT (h264parse, "insufficient data to split input");
return GST_FLOW_NOT_NEGOTIATED;
}
parse_failed:
{
if (h264parse->split_packetized) {
GST_ELEMENT_ERROR (h264parse, STREAM, FAILED, (NULL),
("invalid AVC input data"));
return GST_FLOW_ERROR;
} else {
/* do not meddle to much in this case */
GST_DEBUG_OBJECT (h264parse, "parsing packet failed");
goto exit;
}
}
}
static gboolean
gst_h264_parse_set_caps (GstBaseParse * parse, GstCaps * caps)
{
GstH264Parse *h264parse;
GstStructure *str;
const GValue *value;
GstBuffer *codec_data = NULL;
guint size, format, align;
h264parse = GST_H264_PARSE (parse);
/* reset */
h264parse->push_codec = FALSE;
str = gst_caps_get_structure (caps, 0);
/* accept upstream info if provided */
gst_structure_get_int (str, "width", &h264parse->width);
gst_structure_get_int (str, "height", &h264parse->height);
gst_structure_get_fraction (str, "framerate", &h264parse->fps_num,
&h264parse->fps_den);
/* get upstream format and align from caps */
gst_h264_parse_format_from_caps (caps, &format, &align);
/* packetized video has a codec_data */
if (format != GST_H264_PARSE_FORMAT_BYTE &&
(value = gst_structure_get_value (str, "codec_data"))) {
guint8 *data;
guint num_sps, num_pps, profile, len;
gint i;
GST_DEBUG_OBJECT (h264parse, "have packetized h264");
/* make note for optional split processing */
h264parse->packetized = TRUE;
codec_data = gst_value_get_buffer (value);
if (!codec_data)
goto wrong_type;
data = GST_BUFFER_DATA (codec_data);
size = GST_BUFFER_SIZE (codec_data);
/* 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);
num_sps = data[5] & 0x1f;
data += 6;
size -= 6;
for (i = 0; i < num_sps; i++) {
len = GST_READ_UINT16_BE (data);
if (size < len + 2 || len < 2)
goto avcc_too_small;
/* digest for later reference */
gst_h264_parse_process_nal (h264parse, data, 0, 2, len);
data += len + 2;
size -= len + 2;
}
num_pps = data[0];
data++;
size++;
for (i = 0; i < num_pps; i++) {
len = GST_READ_UINT16_BE (data);
if (size < len + 2 || len < 2)
goto avcc_too_small;
/* digest for later reference */
gst_h264_parse_process_nal (h264parse, data, 0, 2, len);
data += len + 2;
size -= len + 2;
}
h264parse->codec_data = gst_buffer_ref (codec_data);
/* if upstream sets codec_data without setting stream-format and alignment, we
* assume stream-format=avc,alignment=au */
if (format == GST_H264_PARSE_FORMAT_NONE) {
format = GST_H264_PARSE_FORMAT_AVC;
align = GST_H264_PARSE_ALIGN_AU;
}
} else {
GST_DEBUG_OBJECT (h264parse, "have bytestream h264");
/* nothing to pre-process */
h264parse->packetized = FALSE;
/* we have 4 sync bytes */
h264parse->nal_length_size = 4;
if (format == GST_H264_PARSE_FORMAT_NONE) {
format = GST_H264_PARSE_FORMAT_BYTE;
align = GST_H264_PARSE_ALIGN_AU;
}
}
/* negotiate with downstream, sets ->format and ->align */
gst_h264_parse_negotiate (h264parse);
if (format == h264parse->format && align == h264parse->align) {
gst_base_parse_set_passthrough (parse, TRUE);
/* we did parse codec-data and might supplement src caps */
gst_h264_parse_update_src_caps (h264parse, caps);
} else if (format == GST_H264_PARSE_FORMAT_AVC) {
/* if input != output, and input is avc, must split before anything else */
/* arrange to insert codec-data in-stream if needed.
* src caps are only arranged for later on */
h264parse->push_codec = TRUE;
h264parse->split_packetized = TRUE;
h264parse->packetized = TRUE;
}
return TRUE;
/* ERRORS */
avcc_too_small:
{
GST_DEBUG_OBJECT (h264parse, "avcC size %u < 7", size);
goto refuse_caps;
}
wrong_version:
{
GST_DEBUG_OBJECT (h264parse, "wrong avcC version");
goto refuse_caps;
}
wrong_type:
{
GST_DEBUG_OBJECT (h264parse, "wrong codec-data type");
goto refuse_caps;
}
unknown_input_format:
{
GST_DEBUG_OBJECT (h264parse, "unknown stream-format and no codec_data");
goto refuse_caps;
}
refuse_caps:
{
GST_WARNING_OBJECT (h264parse, "refused caps %" GST_PTR_FORMAT, caps);
return FALSE;
}
}
static gboolean
gst_h264_parse_check_valid_frame (GstBaseParse * parse,
GstBaseParseFrame * frame, guint * framesize, gint * skipsize)
{
GstH264Parse *h264parse = GST_H264_PARSE (parse);
GstBuffer *buffer = frame->buffer;
gint sc_pos, nal_pos, next_sc_pos, next_nal_pos;
guint8 *data;
guint size;
gboolean drain;
/* expect at least 3 bytes startcode == sc, and 2 bytes NALU payload */
if (G_UNLIKELY (GST_BUFFER_SIZE (buffer) < 5))
return FALSE;
/* need to configure aggregation */
if (G_UNLIKELY (h264parse->format == GST_H264_PARSE_FORMAT_NONE))
gst_h264_parse_negotiate (h264parse);
/* avoid stale cached parsing state */
if (!(frame->flags & GST_BASE_PARSE_FRAME_FLAG_PARSING)) {
GST_LOG_OBJECT (h264parse, "parsing new frame");
gst_h264_parse_reset_frame (h264parse);
frame->flags |= GST_BASE_PARSE_FRAME_FLAG_PARSING;
} else {
GST_LOG_OBJECT (h264parse, "resuming frame parsing");
}
data = GST_BUFFER_DATA (buffer);
size = GST_BUFFER_SIZE (buffer);
GST_LOG_OBJECT (h264parse, "last_nal_pos: %d, last_scan_pos %d",
h264parse->last_nal_pos, h264parse->next_sc_pos);
nal_pos = h264parse->last_nal_pos;
next_sc_pos = h264parse->next_sc_pos;
if (!next_sc_pos) {
sc_pos = gst_h264_parse_find_sc (buffer, 0);
if (sc_pos == -1) {
/* SC not found, need more data */
sc_pos = GST_BUFFER_SIZE (buffer) - 3;
/* avoid going < 0 later on */
nal_pos = next_sc_pos = sc_pos;
goto more;
}
nal_pos = sc_pos + 3;
next_sc_pos = nal_pos;
/* sc might have 2 or 3 0-bytes */
if (sc_pos > 0 && data[sc_pos - 1] == 00)
sc_pos--;
GST_LOG_OBJECT (h264parse, "found sc at offset %d", sc_pos);
} else {
/* previous checks already arrange sc at start */
sc_pos = 0;
}
drain = GST_BASE_PARSE_DRAINING (parse);
while (TRUE) {
gint prev_sc_pos;
next_sc_pos = gst_h264_parse_find_sc (buffer, next_sc_pos);
if (next_sc_pos == -1) {
GST_LOG_OBJECT (h264parse, "no next sc");
if (drain) {
/* FLUSH/EOS, it's okay if we can't find the next frame */
next_sc_pos = size;
next_nal_pos = size;
} else {
next_sc_pos = size - 3;
goto more;
}
} else {
next_nal_pos = next_sc_pos + 3;
if (data[next_sc_pos - 1] == 00)
next_sc_pos--;
GST_LOG_OBJECT (h264parse, "found next sc at offset %d", next_sc_pos);
/* need at least 1 more byte of next NAL */
if (!drain && (next_nal_pos == size - 1))
goto more;
}
/* determine nal's sc position */
prev_sc_pos = nal_pos - 3;
g_assert (prev_sc_pos >= 0);
if (prev_sc_pos > 0 && data[prev_sc_pos - 1] == 0)
prev_sc_pos--;
/* already consume and gather info from NAL */
if (G_UNLIKELY (next_sc_pos - nal_pos < 2)) {
GST_WARNING_OBJECT (h264parse, "input stream is corrupt; "
"it contains a NAL unit of length %d", next_sc_pos - nal_pos);
/* broken nal at start -> arrange to skip it,
* otherwise have it terminate current au
* (and so it will be skippd on next frame round) */
if (prev_sc_pos == sc_pos) {
*skipsize = sc_pos + 2;
return FALSE;
} else {
next_sc_pos = prev_sc_pos;
break;
}
}
gst_h264_parse_process_nal (h264parse, data, prev_sc_pos, nal_pos,
next_sc_pos - nal_pos);
if (next_nal_pos >= size - 1 ||
gst_h264_parse_collect_nal (h264parse, data + nal_pos,
data + next_nal_pos))
break;
/* move along */
next_sc_pos = nal_pos = next_nal_pos;
}
*skipsize = sc_pos;
*framesize = next_sc_pos - sc_pos;
return TRUE;
more:
/* ask for best next available */
*framesize = G_MAXUINT;
/* skip up to initial startcode */
*skipsize = sc_pos;
/* resume scanning here next time */
h264parse->last_nal_pos = nal_pos - sc_pos;
h264parse->next_sc_pos = next_sc_pos - sc_pos;
return FALSE;
}
