static GstFlowReturn
gst_h263_parse_parse_frame (GstBaseParse * parse, GstBaseParseFrame * frame)
{
GstH263Parse *h263parse;
GstBuffer *buffer;
GstFlowReturn res;
H263Params params = { 0, };
h263parse = GST_H263_PARSE (parse);
buffer = frame->buffer;
res = gst_h263_parse_get_params (¶ms, buffer, TRUE, &h263parse->state);
if (res != GST_FLOW_OK)
goto out;
if (h263parse->state == PASSTHROUGH || h263parse->state == PARSING) {
/* There's a feature we don't support, or we didn't have enough data to
* parse the header, which should not be possible. Either way, go into
* passthrough mode and let downstream handle it if it can. */
GST_WARNING ("Couldn't parse header - setting passthrough mode");
gst_base_parse_set_passthrough (parse, TRUE);
goto out;
}
/* h263parse->state is now GOT_HEADER */
gst_buffer_set_caps (buffer,
GST_PAD_CAPS (GST_BASE_PARSE_SRC_PAD (GST_BASE_PARSE (h263parse))));
if (gst_h263_parse_is_delta_unit (¶ms))
GST_BUFFER_FLAG_UNSET (buffer, GST_BUFFER_FLAG_DELTA_UNIT);
else
GST_BUFFER_FLAG_SET (buffer, GST_BUFFER_FLAG_DELTA_UNIT);
out:
return res;
}
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_h263_parse_check_valid_frame (GstBaseParse * parse,
GstBaseParseFrame * frame, guint * framesize, gint * skipsize)
{
GstH263Parse *h263parse;
GstBuffer *buffer;
guint psc_pos, next_psc_pos;
h263parse = GST_H263_PARSE (parse);
buffer = frame->buffer;
if (GST_BUFFER_SIZE (buffer) < 3)
return FALSE;
psc_pos = find_psc (buffer, 0);
if (psc_pos == -1) {
/* PSC not found, need more data */
if (GST_BUFFER_SIZE (buffer) > 3)
psc_pos = GST_BUFFER_SIZE (buffer) - 3;
else
psc_pos = 0;
goto more;
}
/* Found the start of the frame, now try to find the end */
next_psc_pos = psc_pos + 3;
next_psc_pos = find_psc (buffer, next_psc_pos);
if (next_psc_pos == -1) {
if (GST_BASE_PARSE_DRAINING (parse))
/* FLUSH/EOS, it's okay if we can't find the next frame */
next_psc_pos = GST_BUFFER_SIZE (buffer);
else
goto more;
}
/* We should now have a complete frame */
/* If this is the first frame, parse and set srcpad caps */
if (h263parse->state == PARSING) {
H263Params params = { 0, };
GstFlowReturn res;
res = gst_h263_parse_get_params (¶ms, buffer, FALSE, &h263parse->state);
if (res != GST_FLOW_OK || h263parse->state != GOT_HEADER) {
GST_WARNING ("Couldn't parse header - setting passthrough mode");
gst_base_parse_set_passthrough (parse, TRUE);
} else {
/* Set srcpad caps since we now have sufficient information to do so */
gst_h263_parse_set_src_caps (h263parse, ¶ms);
gst_base_parse_set_passthrough (parse, FALSE);
}
}
*skipsize = psc_pos;
*framesize = next_psc_pos - psc_pos;
/* XXX: After getting a keyframe, should we adjust min_frame_size to
* something smaller so we don't end up collecting too many non-keyframes? */
GST_DEBUG_OBJECT (h263parse, "found a frame of size %d at pos %d",
*framesize, *skipsize);
return TRUE;
more:
/* ask for best next available */
*framesize = G_MAXUINT;
*skipsize = psc_pos;
return FALSE;
}
static GstFlowReturn
gst_h263_parse_handle_frame (GstBaseParse * parse,
GstBaseParseFrame * frame, gint * skipsize)
{
GstH263Parse *h263parse;
GstBuffer *buffer;
guint psc_pos, next_psc_pos;
gsize size;
H263Params params = { 0, };
GstFlowReturn res = GST_FLOW_OK;
h263parse = GST_H263_PARSE (parse);
buffer = frame->buffer;
size = gst_buffer_get_size (buffer);
if (size < 3) {
*skipsize = 1;
return GST_FLOW_OK;
}
psc_pos = find_psc (buffer, 0);
if (psc_pos == -1) {
/* PSC not found, need more data */
if (size > 3)
psc_pos = size - 3;
else
psc_pos = 0;
goto more;
}
/* need to skip */
if (psc_pos > 0)
goto more;
/* Found the start of the frame, now try to find the end */
next_psc_pos = psc_pos + 3;
next_psc_pos = find_psc (buffer, next_psc_pos);
if (next_psc_pos == -1) {
if (GST_BASE_PARSE_DRAINING (parse))
/* FLUSH/EOS, it's okay if we can't find the next frame */
next_psc_pos = size;
else
goto more;
}
/* We should now have a complete frame */
/* If this is the first frame, parse and set srcpad caps */
if (h263parse->state == PARSING) {
res = gst_h263_parse_get_params (¶ms, buffer, FALSE, &h263parse->state);
if (res != GST_FLOW_OK || h263parse->state != GOT_HEADER) {
GST_WARNING ("Couldn't parse header - setting passthrough mode");
gst_base_parse_set_passthrough (parse, TRUE);
} else {
/* Set srcpad caps since we now have sufficient information to do so */
gst_h263_parse_set_src_caps (h263parse, ¶ms);
gst_base_parse_set_passthrough (parse, FALSE);
}
memset (¶ms, 0, sizeof (params));
}
/* XXX: After getting a keyframe, should we adjust min_frame_size to
* something smaller so we don't end up collecting too many non-keyframes? */
GST_DEBUG_OBJECT (h263parse, "found a frame of size %u at pos %u",
next_psc_pos, psc_pos);
res = gst_h263_parse_get_params (¶ms, buffer, TRUE, &h263parse->state);
if (res != GST_FLOW_OK)
goto more;
if (h263parse->state == PASSTHROUGH || h263parse->state == PARSING) {
/* There's a feature we don't support, or we didn't have enough data to
* parse the header, which should not be possible. Either way, go into
* passthrough mode and let downstream handle it if it can. */
GST_WARNING ("Couldn't parse header - setting passthrough mode");
gst_base_parse_set_passthrough (parse, TRUE);
goto more;
}
if (gst_h263_parse_is_delta_unit (¶ms))
GST_BUFFER_FLAG_UNSET (buffer, GST_BUFFER_FLAG_DELTA_UNIT);
else
GST_BUFFER_FLAG_SET (buffer, GST_BUFFER_FLAG_DELTA_UNIT);
return gst_base_parse_finish_frame (parse, frame, next_psc_pos);
more:
*skipsize = psc_pos;
return res;
}
