gstreamer/subprojects/gst-plugins-good/gst/rtp/gstrtpjpegdepay.c

795 lines
24 KiB
C

/* GStreamer
* Copyright (C) <2008> Wim Taymans <wim.taymans@gmail.com>
*
* 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/rtp/gstrtpbuffer.h>
#include <gst/video/video.h>
#include <math.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "gstrtpelements.h"
#include "gstrtpjpegdepay.h"
#include "gstrtputils.h"
GST_DEBUG_CATEGORY_STATIC (rtpjpegdepay_debug);
#define GST_CAT_DEFAULT (rtpjpegdepay_debug)
static GstStaticPadTemplate gst_rtp_jpeg_depay_src_template =
GST_STATIC_PAD_TEMPLATE ("src",
GST_PAD_SRC,
GST_PAD_ALWAYS,
GST_STATIC_CAPS ("image/jpeg")
);
static GstStaticPadTemplate gst_rtp_jpeg_depay_sink_template =
GST_STATIC_PAD_TEMPLATE ("sink",
GST_PAD_SINK,
GST_PAD_ALWAYS,
GST_STATIC_CAPS ("application/x-rtp, "
"media = (string) \"video\", "
"clock-rate = (int) 90000, " "encoding-name = (string) \"JPEG\"; "
/* optional SDP attributes */
/*
* "a-framerate = (string) 0.00, "
* "x-framerate = (string) 0.00, "
* "x-dimensions = (string) \"1234,1234\", "
*/
"application/x-rtp, "
"media = (string) \"video\", "
"payload = (int) " GST_RTP_PAYLOAD_JPEG_STRING ", "
"clock-rate = (int) 90000"
/* optional SDP attributes */
/*
* "a-framerate = (string) 0.00, "
* "x-framerate = (string) 0.00, "
* "x-dimensions = (string) \"1234,1234\""
*/
)
);
#define gst_rtp_jpeg_depay_parent_class parent_class
G_DEFINE_TYPE (GstRtpJPEGDepay, gst_rtp_jpeg_depay,
GST_TYPE_RTP_BASE_DEPAYLOAD);
GST_ELEMENT_REGISTER_DEFINE_WITH_CODE (rtpjpegdepay, "rtpjpegdepay",
GST_RANK_SECONDARY, GST_TYPE_RTP_JPEG_DEPAY, rtp_element_init (plugin));
static void gst_rtp_jpeg_depay_finalize (GObject * object);
static GstStateChangeReturn gst_rtp_jpeg_depay_change_state (GstElement *
element, GstStateChange transition);
static gboolean gst_rtp_jpeg_depay_setcaps (GstRTPBaseDepayload * depayload,
GstCaps * caps);
static GstBuffer *gst_rtp_jpeg_depay_process (GstRTPBaseDepayload * depayload,
GstRTPBuffer * rtp);
static void
gst_rtp_jpeg_depay_class_init (GstRtpJPEGDepayClass * klass)
{
GObjectClass *gobject_class;
GstElementClass *gstelement_class;
GstRTPBaseDepayloadClass *gstrtpbasedepayload_class;
gobject_class = (GObjectClass *) klass;
gstelement_class = (GstElementClass *) klass;
gstrtpbasedepayload_class = (GstRTPBaseDepayloadClass *) klass;
gobject_class->finalize = gst_rtp_jpeg_depay_finalize;
gst_element_class_add_static_pad_template (gstelement_class,
&gst_rtp_jpeg_depay_src_template);
gst_element_class_add_static_pad_template (gstelement_class,
&gst_rtp_jpeg_depay_sink_template);
gst_element_class_set_static_metadata (gstelement_class,
"RTP JPEG depayloader", "Codec/Depayloader/Network/RTP",
"Extracts JPEG video from RTP packets (RFC 2435)",
"Wim Taymans <wim.taymans@gmail.com>");
gstelement_class->change_state = gst_rtp_jpeg_depay_change_state;
gstrtpbasedepayload_class->set_caps = gst_rtp_jpeg_depay_setcaps;
gstrtpbasedepayload_class->process_rtp_packet = gst_rtp_jpeg_depay_process;
GST_DEBUG_CATEGORY_INIT (rtpjpegdepay_debug, "rtpjpegdepay", 0,
"JPEG Video RTP Depayloader");
}
static void
gst_rtp_jpeg_depay_init (GstRtpJPEGDepay * rtpjpegdepay)
{
rtpjpegdepay->adapter = gst_adapter_new ();
}
static void
gst_rtp_jpeg_depay_reset (GstRtpJPEGDepay * depay)
{
gint i;
depay->width = 0;
depay->height = 0;
depay->media_width = 0;
depay->media_height = 0;
depay->frate_num = 0;
depay->frate_denom = 1;
depay->discont = TRUE;
for (i = 0; i < 255; i++) {
g_free (depay->qtables[i]);
depay->qtables[i] = NULL;
}
gst_adapter_clear (depay->adapter);
}
static void
gst_rtp_jpeg_depay_finalize (GObject * object)
{
GstRtpJPEGDepay *rtpjpegdepay;
rtpjpegdepay = GST_RTP_JPEG_DEPAY (object);
gst_rtp_jpeg_depay_reset (rtpjpegdepay);
g_object_unref (rtpjpegdepay->adapter);
rtpjpegdepay->adapter = NULL;
G_OBJECT_CLASS (parent_class)->finalize (object);
}
static const int zigzag[] = {
0, 1, 8, 16, 9, 2, 3, 10,
17, 24, 32, 25, 18, 11, 4, 5,
12, 19, 26, 33, 40, 48, 41, 34,
27, 20, 13, 6, 7, 14, 21, 28,
35, 42, 49, 56, 57, 50, 43, 36,
29, 22, 15, 23, 30, 37, 44, 51,
58, 59, 52, 45, 38, 31, 39, 46,
53, 60, 61, 54, 47, 55, 62, 63
};
/*
* Table K.1 from JPEG spec.
*/
static const int jpeg_luma_quantizer[64] = {
16, 11, 10, 16, 24, 40, 51, 61,
12, 12, 14, 19, 26, 58, 60, 55,
14, 13, 16, 24, 40, 57, 69, 56,
14, 17, 22, 29, 51, 87, 80, 62,
18, 22, 37, 56, 68, 109, 103, 77,
24, 35, 55, 64, 81, 104, 113, 92,
49, 64, 78, 87, 103, 121, 120, 101,
72, 92, 95, 98, 112, 100, 103, 99
};
/*
* Table K.2 from JPEG spec.
*/
static const int jpeg_chroma_quantizer[64] = {
17, 18, 24, 47, 99, 99, 99, 99,
18, 21, 26, 66, 99, 99, 99, 99,
24, 26, 56, 99, 99, 99, 99, 99,
47, 66, 99, 99, 99, 99, 99, 99,
99, 99, 99, 99, 99, 99, 99, 99,
99, 99, 99, 99, 99, 99, 99, 99,
99, 99, 99, 99, 99, 99, 99, 99,
99, 99, 99, 99, 99, 99, 99, 99
};
/* Call MakeTables with the Q factor and a guint8[128] return array
*/
static void
MakeTables (GstRtpJPEGDepay * rtpjpegdepay, gint Q, guint8 qtable[128])
{
gint i;
guint factor;
factor = CLAMP (Q, 1, 99);
if (Q < 50)
Q = 5000 / factor;
else
Q = 200 - factor * 2;
for (i = 0; i < 64; i++) {
gint lq = (jpeg_luma_quantizer[zigzag[i]] * Q + 50) / 100;
gint cq = (jpeg_chroma_quantizer[zigzag[i]] * Q + 50) / 100;
/* Limit the quantizers to 1 <= q <= 255 */
qtable[i] = CLAMP (lq, 1, 255);
qtable[i + 64] = CLAMP (cq, 1, 255);
}
}
static const guint8 lum_dc_codelens[] = {
0, 1, 5, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0
};
static const guint8 lum_dc_symbols[] = {
0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11
};
static const guint8 lum_ac_codelens[] = {
0, 2, 1, 3, 3, 2, 4, 3, 5, 5, 4, 4, 0, 0, 1, 0x7d
};
static const guint8 lum_ac_symbols[] = {
0x01, 0x02, 0x03, 0x00, 0x04, 0x11, 0x05, 0x12,
0x21, 0x31, 0x41, 0x06, 0x13, 0x51, 0x61, 0x07,
0x22, 0x71, 0x14, 0x32, 0x81, 0x91, 0xa1, 0x08,
0x23, 0x42, 0xb1, 0xc1, 0x15, 0x52, 0xd1, 0xf0,
0x24, 0x33, 0x62, 0x72, 0x82, 0x09, 0x0a, 0x16,
0x17, 0x18, 0x19, 0x1a, 0x25, 0x26, 0x27, 0x28,
0x29, 0x2a, 0x34, 0x35, 0x36, 0x37, 0x38, 0x39,
0x3a, 0x43, 0x44, 0x45, 0x46, 0x47, 0x48, 0x49,
0x4a, 0x53, 0x54, 0x55, 0x56, 0x57, 0x58, 0x59,
0x5a, 0x63, 0x64, 0x65, 0x66, 0x67, 0x68, 0x69,
0x6a, 0x73, 0x74, 0x75, 0x76, 0x77, 0x78, 0x79,
0x7a, 0x83, 0x84, 0x85, 0x86, 0x87, 0x88, 0x89,
0x8a, 0x92, 0x93, 0x94, 0x95, 0x96, 0x97, 0x98,
0x99, 0x9a, 0xa2, 0xa3, 0xa4, 0xa5, 0xa6, 0xa7,
0xa8, 0xa9, 0xaa, 0xb2, 0xb3, 0xb4, 0xb5, 0xb6,
0xb7, 0xb8, 0xb9, 0xba, 0xc2, 0xc3, 0xc4, 0xc5,
0xc6, 0xc7, 0xc8, 0xc9, 0xca, 0xd2, 0xd3, 0xd4,
0xd5, 0xd6, 0xd7, 0xd8, 0xd9, 0xda, 0xe1, 0xe2,
0xe3, 0xe4, 0xe5, 0xe6, 0xe7, 0xe8, 0xe9, 0xea,
0xf1, 0xf2, 0xf3, 0xf4, 0xf5, 0xf6, 0xf7, 0xf8,
0xf9, 0xfa
};
static const guint8 chm_dc_codelens[] = {
0, 3, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0
};
static const guint8 chm_dc_symbols[] = {
0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11
};
static const guint8 chm_ac_codelens[] = {
0, 2, 1, 2, 4, 4, 3, 4, 7, 5, 4, 4, 0, 1, 2, 0x77
};
static const guint8 chm_ac_symbols[] = {
0x00, 0x01, 0x02, 0x03, 0x11, 0x04, 0x05, 0x21,
0x31, 0x06, 0x12, 0x41, 0x51, 0x07, 0x61, 0x71,
0x13, 0x22, 0x32, 0x81, 0x08, 0x14, 0x42, 0x91,
0xa1, 0xb1, 0xc1, 0x09, 0x23, 0x33, 0x52, 0xf0,
0x15, 0x62, 0x72, 0xd1, 0x0a, 0x16, 0x24, 0x34,
0xe1, 0x25, 0xf1, 0x17, 0x18, 0x19, 0x1a, 0x26,
0x27, 0x28, 0x29, 0x2a, 0x35, 0x36, 0x37, 0x38,
0x39, 0x3a, 0x43, 0x44, 0x45, 0x46, 0x47, 0x48,
0x49, 0x4a, 0x53, 0x54, 0x55, 0x56, 0x57, 0x58,
0x59, 0x5a, 0x63, 0x64, 0x65, 0x66, 0x67, 0x68,
0x69, 0x6a, 0x73, 0x74, 0x75, 0x76, 0x77, 0x78,
0x79, 0x7a, 0x82, 0x83, 0x84, 0x85, 0x86, 0x87,
0x88, 0x89, 0x8a, 0x92, 0x93, 0x94, 0x95, 0x96,
0x97, 0x98, 0x99, 0x9a, 0xa2, 0xa3, 0xa4, 0xa5,
0xa6, 0xa7, 0xa8, 0xa9, 0xaa, 0xb2, 0xb3, 0xb4,
0xb5, 0xb6, 0xb7, 0xb8, 0xb9, 0xba, 0xc2, 0xc3,
0xc4, 0xc5, 0xc6, 0xc7, 0xc8, 0xc9, 0xca, 0xd2,
0xd3, 0xd4, 0xd5, 0xd6, 0xd7, 0xd8, 0xd9, 0xda,
0xe2, 0xe3, 0xe4, 0xe5, 0xe6, 0xe7, 0xe8, 0xe9,
0xea, 0xf2, 0xf3, 0xf4, 0xf5, 0xf6, 0xf7, 0xf8,
0xf9, 0xfa
};
static guint8 *
MakeQuantHeader (guint8 * p, guint8 * qt, gint size, gint tableNo)
{
*p++ = 0xff;
*p++ = 0xdb; /* DQT */
*p++ = 0; /* length msb */
*p++ = size + 3; /* length lsb */
*p++ = tableNo;
memcpy (p, qt, size);
return (p + size);
}
static guint8 *
MakeHuffmanHeader (guint8 * p, const guint8 * codelens, int ncodes,
const guint8 * symbols, int nsymbols, int tableNo, int tableClass)
{
*p++ = 0xff;
*p++ = 0xc4; /* DHT */
*p++ = 0; /* length msb */
*p++ = 3 + ncodes + nsymbols; /* length lsb */
*p++ = (tableClass << 4) | tableNo;
memcpy (p, codelens, ncodes);
p += ncodes;
memcpy (p, symbols, nsymbols);
p += nsymbols;
return (p);
}
static guint8 *
MakeDRIHeader (guint8 * p, guint16 dri)
{
*p++ = 0xff;
*p++ = 0xdd; /* DRI */
*p++ = 0x0; /* length msb */
*p++ = 4; /* length lsb */
*p++ = dri >> 8; /* dri msb */
*p++ = dri & 0xff; /* dri lsb */
return (p);
}
/*
* Arguments:
* type, width, height: as supplied in RTP/JPEG header
* qt: quantization tables as either derived from
* the Q field using MakeTables() or as specified
* in section 4.2.
* dri: restart interval in MCUs, or 0 if no restarts.
*
* p: pointer to return area
*
* Return value:
* The length of the generated headers.
*
* Generate a frame and scan headers that can be prepended to the
* RTP/JPEG data payload to produce a JPEG compressed image in
* interchange format (except for possible trailing garbage and
* absence of an EOI marker to terminate the scan).
*/
static guint
MakeHeaders (guint8 * p, int type, int width, int height, guint8 * qt,
guint precision, guint16 dri)
{
guint8 *start = p;
gint size;
*p++ = 0xff;
*p++ = 0xd8; /* SOI */
size = ((precision & 1) ? 128 : 64);
p = MakeQuantHeader (p, qt, size, 0);
qt += size;
size = ((precision & 2) ? 128 : 64);
p = MakeQuantHeader (p, qt, size, 1);
qt += size;
if (dri != 0)
p = MakeDRIHeader (p, dri);
*p++ = 0xff;
*p++ = 0xc0; /* SOF */
*p++ = 0; /* length msb */
*p++ = 17; /* length lsb */
*p++ = 8; /* 8-bit precision */
*p++ = height >> 8; /* height msb */
*p++ = height; /* height lsb */
*p++ = width >> 8; /* width msb */
*p++ = width; /* width lsb */
*p++ = 3; /* number of components */
*p++ = 0; /* comp 0 */
if ((type & 0x3f) == 0)
*p++ = 0x21; /* hsamp = 2, vsamp = 1 */
else
*p++ = 0x22; /* hsamp = 2, vsamp = 2 */
*p++ = 0; /* quant table 0 */
*p++ = 1; /* comp 1 */
*p++ = 0x11; /* hsamp = 1, vsamp = 1 */
*p++ = 1; /* quant table 1 */
*p++ = 2; /* comp 2 */
*p++ = 0x11; /* hsamp = 1, vsamp = 1 */
*p++ = 1; /* quant table 1 */
p = MakeHuffmanHeader (p, lum_dc_codelens,
sizeof (lum_dc_codelens), lum_dc_symbols, sizeof (lum_dc_symbols), 0, 0);
p = MakeHuffmanHeader (p, lum_ac_codelens,
sizeof (lum_ac_codelens), lum_ac_symbols, sizeof (lum_ac_symbols), 0, 1);
p = MakeHuffmanHeader (p, chm_dc_codelens,
sizeof (chm_dc_codelens), chm_dc_symbols, sizeof (chm_dc_symbols), 1, 0);
p = MakeHuffmanHeader (p, chm_ac_codelens,
sizeof (chm_ac_codelens), chm_ac_symbols, sizeof (chm_ac_symbols), 1, 1);
*p++ = 0xff;
*p++ = 0xda; /* SOS */
*p++ = 0; /* length msb */
*p++ = 12; /* length lsb */
*p++ = 3; /* 3 components */
*p++ = 0; /* comp 0 */
*p++ = 0; /* huffman table 0 */
*p++ = 1; /* comp 1 */
*p++ = 0x11; /* huffman table 1 */
*p++ = 2; /* comp 2 */
*p++ = 0x11; /* huffman table 1 */
*p++ = 0; /* first DCT coeff */
*p++ = 63; /* last DCT coeff */
*p++ = 0; /* successive approx. */
return (p - start);
};
static gboolean
gst_rtp_jpeg_depay_setcaps (GstRTPBaseDepayload * depayload, GstCaps * caps)
{
GstRtpJPEGDepay *rtpjpegdepay;
GstStructure *structure;
gint clock_rate;
const gchar *media_attr;
rtpjpegdepay = GST_RTP_JPEG_DEPAY (depayload);
structure = gst_caps_get_structure (caps, 0);
GST_DEBUG_OBJECT (rtpjpegdepay, "Caps set: %" GST_PTR_FORMAT, caps);
if (!gst_structure_get_int (structure, "clock-rate", &clock_rate))
clock_rate = 90000;
depayload->clock_rate = clock_rate;
/* reset defaults */
rtpjpegdepay->width = 0;
rtpjpegdepay->height = 0;
rtpjpegdepay->media_width = 0;
rtpjpegdepay->media_height = 0;
rtpjpegdepay->frate_num = 0;
rtpjpegdepay->frate_denom = 1;
/* check for optional SDP attributes */
if ((media_attr = gst_structure_get_string (structure, "x-dimensions"))) {
gint w, h;
if (sscanf (media_attr, "%d,%d", &w, &h) == 2) {
rtpjpegdepay->media_width = w;
rtpjpegdepay->media_height = h;
}
}
/* try to get a framerate */
media_attr = gst_structure_get_string (structure, "a-framerate");
if (!media_attr)
media_attr = gst_structure_get_string (structure, "x-framerate");
if (media_attr) {
GValue src = { 0 };
GValue dest = { 0 };
gchar *s;
/* canonicalise floating point string so we can handle framerate strings
* in the form "24.930" or "24,930" irrespective of the current locale */
s = g_strdup (media_attr);
g_strdelimit (s, ",", '.');
/* convert the float to a fraction */
g_value_init (&src, G_TYPE_DOUBLE);
g_value_set_double (&src, g_ascii_strtod (s, NULL));
g_value_init (&dest, GST_TYPE_FRACTION);
g_value_transform (&src, &dest);
rtpjpegdepay->frate_num = gst_value_get_fraction_numerator (&dest);
rtpjpegdepay->frate_denom = gst_value_get_fraction_denominator (&dest);
g_free (s);
}
return TRUE;
}
static GstBuffer *
gst_rtp_jpeg_depay_process (GstRTPBaseDepayload * depayload, GstRTPBuffer * rtp)
{
GstRtpJPEGDepay *rtpjpegdepay;
GstBuffer *outbuf;
gint payload_len, header_len;
guint8 *payload;
guint frag_offset;
gint Q;
guint type, width, height;
guint16 dri, precision, length;
guint8 *qtable;
rtpjpegdepay = GST_RTP_JPEG_DEPAY (depayload);
if (GST_BUFFER_IS_DISCONT (rtp->buffer)) {
GST_DEBUG_OBJECT (depayload, "DISCONT, reset adapter");
gst_adapter_clear (rtpjpegdepay->adapter);
rtpjpegdepay->discont = TRUE;
}
payload_len = gst_rtp_buffer_get_payload_len (rtp);
if (payload_len < 8)
goto empty_packet;
payload = gst_rtp_buffer_get_payload (rtp);
header_len = 0;
/* 0 1 2 3
* 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | Type-specific | Fragment Offset |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | Type | Q | Width | Height |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
*/
frag_offset = (payload[1] << 16) | (payload[2] << 8) | payload[3];
type = payload[4];
Q = payload[5];
width = payload[6] * 8;
height = payload[7] * 8;
/* saw a packet with fragment offset > 0 and we don't already have data queued
* up (most importantly, we don't have a header for this data) -- drop it
* XXX: maybe we can check if the jpeg is progressive and salvage the data?
* XXX: not implemented yet because jpegenc can't create progressive jpegs */
if (frag_offset > 0 && gst_adapter_available (rtpjpegdepay->adapter) == 0)
goto no_header_packet;
/* allow frame dimensions > 2040, passed in SDP session or media attributes
* from gstrtspsrc.c (gst_rtspsrc_sdp_attributes_to_caps), or in caps */
if (!width)
width = rtpjpegdepay->media_width;
if (!height)
height = rtpjpegdepay->media_height;
if (width == 0 || height == 0)
goto invalid_dimension;
GST_DEBUG_OBJECT (rtpjpegdepay, "frag %u, type %u, Q %d, width %u, height %u",
frag_offset, type, Q, width, height);
header_len += 8;
payload += 8;
payload_len -= 8;
dri = 0;
if (type > 63) {
if (payload_len < 4)
goto empty_packet;
/* 0 1 2 3
* 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | Restart Interval |F|L| Restart Count |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
*/
dri = (payload[0] << 8) | payload[1];
GST_DEBUG_OBJECT (rtpjpegdepay, "DRI %" G_GUINT16_FORMAT, dri);
payload += 4;
header_len += 4;
payload_len -= 4;
}
if (Q >= 128 && frag_offset == 0) {
if (payload_len < 4)
goto empty_packet;
/* 0 1 2 3
* 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | MBZ | Precision | Length |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | Quantization Table Data |
* | ... |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
*/
precision = payload[1];
length = (payload[2] << 8) | payload[3];
GST_DEBUG_OBJECT (rtpjpegdepay, "precision %04x, length %" G_GUINT16_FORMAT,
precision, length);
if (Q == 255 && length == 0)
goto empty_packet;
payload += 4;
header_len += 4;
payload_len -= 4;
if (length > payload_len)
goto empty_packet;
if (length > 0)
qtable = payload;
else
qtable = rtpjpegdepay->qtables[Q];
payload += length;
header_len += length;
payload_len -= length;
} else {
length = 0;
qtable = NULL;
precision = 0;
}
if (frag_offset == 0) {
GstMapInfo map;
guint size;
if (rtpjpegdepay->width != width || rtpjpegdepay->height != height) {
GstCaps *outcaps;
outcaps =
gst_caps_new_simple ("image/jpeg", "parsed", G_TYPE_BOOLEAN, TRUE,
"framerate", GST_TYPE_FRACTION, rtpjpegdepay->frate_num,
rtpjpegdepay->frate_denom, "width", G_TYPE_INT, width,
"height", G_TYPE_INT, height, NULL);
gst_pad_set_caps (depayload->srcpad, outcaps);
gst_caps_unref (outcaps);
rtpjpegdepay->width = width;
rtpjpegdepay->height = height;
}
GST_LOG_OBJECT (rtpjpegdepay, "first packet, length %" G_GUINT16_FORMAT,
length);
/* first packet */
if (length == 0) {
if (Q < 128) {
/* no quant table, see if we have one cached */
qtable = rtpjpegdepay->qtables[Q];
if (!qtable) {
GST_DEBUG_OBJECT (rtpjpegdepay, "making Q %d table", Q);
/* make and cache the table */
qtable = g_new (guint8, 128);
MakeTables (rtpjpegdepay, Q, qtable);
rtpjpegdepay->qtables[Q] = qtable;
} else {
GST_DEBUG_OBJECT (rtpjpegdepay, "using cached table for Q %d", Q);
}
/* all 8 bit quantizers */
precision = 0;
} else {
if (!qtable)
goto no_qtable;
}
}
/* I think we can get here with a NULL qtable, so make sure we don't
go dereferencing it in MakeHeaders if we do */
if (!qtable)
goto no_qtable;
/* max header length, should be big enough */
outbuf = gst_buffer_new_and_alloc (1000);
gst_buffer_map (outbuf, &map, GST_MAP_WRITE);
size = MakeHeaders (map.data, type, width, height, qtable, precision, dri);
gst_buffer_unmap (outbuf, &map);
gst_buffer_resize (outbuf, 0, size);
GST_DEBUG_OBJECT (rtpjpegdepay, "pushing %u bytes of header", size);
gst_adapter_push (rtpjpegdepay->adapter, outbuf);
}
/* take JPEG data, push in the adapter */
GST_DEBUG_OBJECT (rtpjpegdepay, "pushing data at offset %d", header_len);
outbuf = gst_rtp_buffer_get_payload_subbuffer (rtp, header_len, -1);
gst_adapter_push (rtpjpegdepay->adapter, outbuf);
outbuf = NULL;
if (gst_rtp_buffer_get_marker (rtp)) {
guint avail;
guint8 end[2];
GstMapInfo map;
/* last buffer take all data out of the adapter */
avail = gst_adapter_available (rtpjpegdepay->adapter);
GST_DEBUG_OBJECT (rtpjpegdepay, "marker set, last buffer");
if (avail < 2)
goto invalid_packet;
/* take the last bytes of the jpeg data to see if there is an EOI
* marker */
gst_adapter_copy (rtpjpegdepay->adapter, end, avail - 2, 2);
if (end[0] != 0xff && end[1] != 0xd9) {
GST_DEBUG_OBJECT (rtpjpegdepay, "no EOI marker, adding one");
/* no EOI marker, add one */
outbuf = gst_buffer_new_and_alloc (2);
gst_buffer_map (outbuf, &map, GST_MAP_WRITE);
map.data[0] = 0xff;
map.data[1] = 0xd9;
gst_buffer_unmap (outbuf, &map);
gst_adapter_push (rtpjpegdepay->adapter, outbuf);
avail += 2;
}
outbuf = gst_adapter_take_buffer (rtpjpegdepay->adapter, avail);
if (rtpjpegdepay->discont) {
GST_BUFFER_FLAG_SET (outbuf, GST_BUFFER_FLAG_DISCONT);
rtpjpegdepay->discont = FALSE;
}
gst_rtp_drop_non_video_meta (rtpjpegdepay, outbuf);
GST_DEBUG_OBJECT (rtpjpegdepay, "returning %u bytes", avail);
}
return outbuf;
/* ERRORS */
empty_packet:
{
GST_ELEMENT_WARNING (rtpjpegdepay, STREAM, DECODE,
("Empty Payload."), (NULL));
return NULL;
}
invalid_dimension:
{
GST_ELEMENT_WARNING (rtpjpegdepay, STREAM, FORMAT,
("Invalid Dimension %dx%d.", width, height), (NULL));
return NULL;
}
no_qtable:
{
GST_WARNING_OBJECT (rtpjpegdepay, "no qtable");
return NULL;
}
invalid_packet:
{
GST_WARNING_OBJECT (rtpjpegdepay, "invalid packet");
gst_adapter_flush (rtpjpegdepay->adapter,
gst_adapter_available (rtpjpegdepay->adapter));
return NULL;
}
no_header_packet:
{
GST_WARNING_OBJECT (rtpjpegdepay,
"discarding data packets received when we have no header");
return NULL;
}
}
static GstStateChangeReturn
gst_rtp_jpeg_depay_change_state (GstElement * element,
GstStateChange transition)
{
GstRtpJPEGDepay *rtpjpegdepay;
GstStateChangeReturn ret;
rtpjpegdepay = GST_RTP_JPEG_DEPAY (element);
switch (transition) {
case GST_STATE_CHANGE_READY_TO_PAUSED:
gst_rtp_jpeg_depay_reset (rtpjpegdepay);
break;
default:
break;
}
ret = GST_ELEMENT_CLASS (parent_class)->change_state (element, transition);
switch (transition) {
case GST_STATE_CHANGE_PAUSED_TO_READY:
break;
default:
break;
}
return ret;
}