/* GStreamer H.263 Parser
* Copyright (C) <2010> Arun Raghavan <arun.raghavan@collabora.co.uk>
* Copyright (C) <2010> Edward Hervey <edward.hervey@collabora.co.uk>
* Copyright (C) <2010> Collabora Multimedia
* Copyright (C) <2010> Nokia Corporation
*
* Some bits C-c,C-v'ed and s/4/3 from h264parse:
* (C) 2005 Michal Benes <michal.benes@itonis.tv>
* (C) 2008 Wim Taymans <wim.taymans@gmail.com>
* (C) 2009 Mark Nauwelaerts <mnauw users sf net>
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with this library; if not, write to the
* Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
* Boston, MA 02110-1301, USA.
*/
#ifdef HAVE_CONFIG_H
# include "config.h"
#endif
#include <gst/base/base.h>
#include <gst/pbutils/pbutils.h>
#include "gsth263parse.h"
#include <string.h>
GST_DEBUG_CATEGORY (h263_parse_debug);
#define GST_CAT_DEFAULT h263_parse_debug
static GstStaticPadTemplate srctemplate =
GST_STATIC_PAD_TEMPLATE ("src", GST_PAD_SRC,
GST_PAD_ALWAYS,
GST_STATIC_CAPS ("video/x-h263, variant = (string) itu, "
"parsed = (boolean) true, framerate=(fraction)[0/1,MAX]")
);
static GstStaticPadTemplate sinktemplate =
GST_STATIC_PAD_TEMPLATE ("sink", GST_PAD_SINK,
GST_PAD_ALWAYS,
GST_STATIC_CAPS ("video/x-h263, variant = (string) itu")
);
#define parent_class gst_h263_parse_parent_class
G_DEFINE_TYPE (GstH263Parse, gst_h263_parse, GST_TYPE_BASE_PARSE);
static gboolean gst_h263_parse_start (GstBaseParse * parse);
static gboolean gst_h263_parse_stop (GstBaseParse * parse);
static gboolean gst_h263_parse_sink_event (GstBaseParse * parse,
GstEvent * event);
static GstFlowReturn gst_h263_parse_handle_frame (GstBaseParse * parse,
GstBaseParseFrame * frame, gint * skipsize);
static GstFlowReturn gst_h263_parse_pre_push_frame (GstBaseParse * parse,
GstBaseParseFrame * frame);
static GstCaps *gst_h263_parse_get_sink_caps (GstBaseParse * parse,
GstCaps * filter);
static void
gst_h263_parse_class_init (GstH263ParseClass * klass)
{
GstElementClass *gstelement_class = GST_ELEMENT_CLASS (klass);
GstBaseParseClass *parse_class = GST_BASE_PARSE_CLASS (klass);
GST_DEBUG_CATEGORY_INIT (h263_parse_debug, "h263parse", 0, "h263 parser");
gst_element_class_add_static_pad_template (gstelement_class, &srctemplate);
gst_element_class_add_static_pad_template (gstelement_class, &sinktemplate);
gst_element_class_set_static_metadata (gstelement_class, "H.263 parser",
"Codec/Parser/Video",
"Parses H.263 streams",
"Arun Raghavan <arun.raghavan@collabora.co.uk>,"
"Edward Hervey <edward.hervey@collabora.co.uk>");
/* Override BaseParse vfuncs */
parse_class->start = GST_DEBUG_FUNCPTR (gst_h263_parse_start);
parse_class->stop = GST_DEBUG_FUNCPTR (gst_h263_parse_stop);
parse_class->sink_event = GST_DEBUG_FUNCPTR (gst_h263_parse_sink_event);
parse_class->handle_frame = GST_DEBUG_FUNCPTR (gst_h263_parse_handle_frame);
parse_class->pre_push_frame =
GST_DEBUG_FUNCPTR (gst_h263_parse_pre_push_frame);
parse_class->get_sink_caps = GST_DEBUG_FUNCPTR (gst_h263_parse_get_sink_caps);
}
static void
gst_h263_parse_init (GstH263Parse * h263parse)
{
GST_PAD_SET_ACCEPT_INTERSECT (GST_BASE_PARSE_SINK_PAD (h263parse));
GST_PAD_SET_ACCEPT_TEMPLATE (GST_BASE_PARSE_SINK_PAD (h263parse));
}
static gboolean
gst_h263_parse_start (GstBaseParse * parse)
{
GstH263Parse *h263parse = GST_H263_PARSE (parse);
GST_DEBUG_OBJECT (h263parse, "start");
h263parse->bitrate = 0;
h263parse->profile = -1;
h263parse->level = -1;
h263parse->state = PARSING;
h263parse->sent_codec_tag = FALSE;
gst_base_parse_set_min_frame_size (parse, 4);
return TRUE;
}
static gboolean
gst_h263_parse_stop (GstBaseParse * parse)
{
GST_DEBUG_OBJECT (parse, "stop");
return TRUE;
}
static gboolean
gst_h263_parse_sink_event (GstBaseParse * parse, GstEvent * event)
{
GstH263Parse *h263parse;
h263parse = GST_H263_PARSE (parse);
switch (GST_EVENT_TYPE (event)) {
case GST_EVENT_TAG:
{
GstTagList *taglist;
gst_event_parse_tag (event, &taglist);
if (gst_tag_list_get_uint (taglist, GST_TAG_BITRATE, &h263parse->bitrate))
GST_DEBUG_OBJECT (h263parse, "got bitrate tag: %u", h263parse->bitrate);
break;
}
default:
break;
}
return GST_BASE_PARSE_CLASS (parent_class)->sink_event (parse, event);
}
static guint
find_psc (GstBuffer * buffer, guint skip)
{
GstMapInfo map;
GstByteReader br;
guint psc_pos = -1, psc;
gst_buffer_map (buffer, &map, GST_MAP_READ);
gst_byte_reader_init (&br, map.data, map.size);
if (!gst_byte_reader_set_pos (&br, skip))
goto out;
if (gst_byte_reader_peek_uint24_be (&br, &psc) == FALSE)
goto out;
/* Scan for the picture start code (22 bits - 0x0020)
* startcode : 0000 0000 0000 0000 1000 00xx
* mask (bin) : 1111 1111 1111 1111 1111 1100
* mask (hex) : f f f f f c
* match : 0 0 0 0 8 0
*/
while ((gst_byte_reader_get_remaining (&br) >= 3)) {
if (gst_byte_reader_peek_uint24_be (&br, &psc) &&
((psc & 0xfffffc) == 0x000080)) {
psc_pos = gst_byte_reader_get_pos (&br);
break;
} else if (gst_byte_reader_skip (&br, 1) == FALSE)
break;
}
out:
gst_buffer_unmap (buffer, &map);
return psc_pos;
}
static void
gst_h263_parse_set_src_caps (GstH263Parse * h263parse,
const H263Params * params)
{
GstStructure *st = NULL;
GstCaps *caps, *sink_caps;
gint fr_num, fr_denom, par_num, par_denom;
g_assert (h263parse->state == PASSTHROUGH || h263parse->state == GOT_HEADER);
caps = gst_pad_get_current_caps (GST_BASE_PARSE_SINK_PAD (h263parse));
if (caps) {
caps = gst_caps_make_writable (caps);
} else {
caps = gst_caps_new_simple ("video/x-h263",
"variant", G_TYPE_STRING, "itu", NULL);
}
gst_caps_set_simple (caps, "parsed", G_TYPE_BOOLEAN, TRUE, NULL);
sink_caps = gst_pad_get_current_caps (GST_BASE_PARSE_SINK_PAD (h263parse));
if (sink_caps && (st = gst_caps_get_structure (sink_caps, 0)) &&
gst_structure_get_fraction (st, "framerate", &fr_num, &fr_denom)) {
/* Got it in caps - nothing more to do */
GST_DEBUG_OBJECT (h263parse, "sink caps override framerate from headers");
} else {
/* Caps didn't have the framerate - get it from params */
gst_h263_parse_get_framerate (params, &fr_num, &fr_denom);
}
gst_caps_set_simple (caps, "framerate", GST_TYPE_FRACTION, fr_num, fr_denom,
NULL);
if (params->width && params->height)
gst_caps_set_simple (caps, "width", G_TYPE_INT, params->width,
"height", G_TYPE_INT, params->height, NULL);
if (st != NULL
&& gst_structure_get_fraction (st, "pixel-aspect-ratio", &par_num,
&par_denom)) {
/* Got it in caps - nothing more to do */
GST_DEBUG_OBJECT (h263parse, "sink caps override PAR");
} else {
/* Caps didn't have the framerate - get it from params */
gst_h263_parse_get_par (params, &par_num, &par_denom);
}
gst_caps_set_simple (caps, "pixel-aspect-ratio", GST_TYPE_FRACTION,
par_num, par_denom, NULL);
if (h263parse->state == GOT_HEADER) {
gst_caps_set_simple (caps,
"annex-d", G_TYPE_BOOLEAN, (params->features & H263_OPTION_UMV_MODE),
"annex-e", G_TYPE_BOOLEAN, (params->features & H263_OPTION_SAC_MODE),
"annex-f", G_TYPE_BOOLEAN, (params->features & H263_OPTION_AP_MODE),
"annex-g", G_TYPE_BOOLEAN, (params->features & H263_OPTION_PB_MODE),
"annex-i", G_TYPE_BOOLEAN, (params->features & H263_OPTION_AIC_MODE),
"annex-j", G_TYPE_BOOLEAN, (params->features & H263_OPTION_DF_MODE),
"annex-k", G_TYPE_BOOLEAN, (params->features & H263_OPTION_SS_MODE),
"annex-m", G_TYPE_BOOLEAN, (params->type == PICTURE_IMPROVED_PB),
"annex-n", G_TYPE_BOOLEAN, (params->features & H263_OPTION_RPS_MODE),
"annex-q", G_TYPE_BOOLEAN, (params->features & H263_OPTION_RRU_MODE),
"annex-r", G_TYPE_BOOLEAN, (params->features & H263_OPTION_ISD_MODE),
"annex-s", G_TYPE_BOOLEAN, (params->features & H263_OPTION_AIV_MODE),
"annex-t", G_TYPE_BOOLEAN, (params->features & H263_OPTION_MQ_MODE),
"annex-u", G_TYPE_BOOLEAN, (params->features & H263_OPTION_ERPS_MODE),
"annex-v", G_TYPE_BOOLEAN, (params->features & H263_OPTION_DPS_MODE),
NULL);
h263parse->profile = gst_h263_parse_get_profile (params);
if (h263parse->profile != -1) {
gchar *profile_str;
profile_str = g_strdup_printf ("%u", h263parse->profile);
gst_caps_set_simple (caps, "profile", G_TYPE_STRING, profile_str, NULL);
g_free (profile_str);
}
h263parse->level = gst_h263_parse_get_level (params, h263parse->profile,
h263parse->bitrate, fr_num, fr_denom);
if (h263parse->level != -1) {
gchar *level_str;
level_str = g_strdup_printf ("%u", h263parse->level);
gst_caps_set_simple (caps, "level", G_TYPE_STRING, level_str, NULL);
g_free (level_str);
}
}
gst_pad_set_caps (GST_BASE_PARSE_SRC_PAD (GST_BASE_PARSE (h263parse)), caps);
gst_caps_unref (caps);
if (sink_caps)
gst_caps_unref (sink_caps);
}
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;
}
static void
remove_fields (GstCaps * caps)
{
guint i, n;
n = gst_caps_get_size (caps);
for (i = 0; i < n; i++) {
GstStructure *s = gst_caps_get_structure (caps, i);
gst_structure_remove_field (s, "parsed");
}
}
static GstCaps *
gst_h263_parse_get_sink_caps (GstBaseParse * parse, GstCaps * filter)
{
GstCaps *peercaps, *templ;
GstCaps *res;
templ = gst_pad_get_pad_template_caps (GST_BASE_PARSE_SINK_PAD (parse));
if (filter) {
GstCaps *fcopy = gst_caps_copy (filter);
/* Remove the fields we convert */
remove_fields (fcopy);
peercaps = gst_pad_peer_query_caps (GST_BASE_PARSE_SRC_PAD (parse), fcopy);
gst_caps_unref (fcopy);
} else
peercaps = gst_pad_peer_query_caps (GST_BASE_PARSE_SRC_PAD (parse), NULL);
if (peercaps) {
/* Remove parsed field */
peercaps = gst_caps_make_writable (peercaps);
remove_fields (peercaps);
res = gst_caps_intersect_full (peercaps, templ, GST_CAPS_INTERSECT_FIRST);
gst_caps_unref (peercaps);
gst_caps_unref (templ);
} else {
res = templ;
}
if (filter) {
GstCaps *intersection;
intersection =
gst_caps_intersect_full (filter, res, GST_CAPS_INTERSECT_FIRST);
gst_caps_unref (res);
res = intersection;
}
return res;
}
static GstFlowReturn
gst_h263_parse_pre_push_frame (GstBaseParse * parse, GstBaseParseFrame * frame)
{
GstH263Parse *h263parse = GST_H263_PARSE (parse);
if (!h263parse->sent_codec_tag) {
GstTagList *taglist;
GstCaps *caps;
/* codec tag */
caps = gst_pad_get_current_caps (GST_BASE_PARSE_SRC_PAD (parse));
if (G_UNLIKELY (caps == NULL)) {
if (GST_PAD_IS_FLUSHING (GST_BASE_PARSE_SRC_PAD (parse))) {
GST_INFO_OBJECT (parse, "Src pad is flushing");
return GST_FLOW_FLUSHING;
} else {
GST_INFO_OBJECT (parse, "Src pad is not negotiated!");
return GST_FLOW_NOT_NEGOTIATED;
}
}
taglist = gst_tag_list_new_empty ();
gst_pb_utils_add_codec_description_to_tag_list (taglist,
GST_TAG_VIDEO_CODEC, caps);
gst_caps_unref (caps);
gst_base_parse_merge_tags (parse, taglist, GST_TAG_MERGE_REPLACE);
gst_tag_list_unref (taglist);
/* also signals the end of first-frame processing */
h263parse->sent_codec_tag = TRUE;
}
return GST_FLOW_OK;
}