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codecparsers: refactor common nal parsing to nalutils

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Moves common code from h264 and h265 to a separate file
This commit is contained in:
Thiago Santos 2014-01-24 01:07:45 -03:00
parent af78b45979
commit 61192a1619
5 changed files with 451 additions and 607 deletions
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4
gst-libs/gst/codecparsers/Makefile.am
View file

@ -2,13 +2,13 @@ lib_LTLIBRARIES = libgstcodecparsers-@GST_API_VERSION@.la
libgstcodecparsers_@GST_API_VERSION@_la_SOURCES = \
gstmpegvideoparser.c gsth264parser.c gstvc1parser.c gstmpeg4parser.c gsth265parser.c \
parserutils.c \
parserutils.c nalutils.c \
gstmpegvideometa.c
libgstcodecparsers_@GST_API_VERSION@includedir = \
$(includedir)/gstreamer-@GST_API_VERSION@/gst/codecparsers
noinst_HEADERS = parserutils.h
noinst_HEADERS = parserutils.h nalutils.h
libgstcodecparsers_@GST_API_VERSION@include_HEADERS = \
gstmpegvideoparser.h gsth264parser.h gstvc1parser.h gstmpeg4parser.h gsth265parser.h \

343
gst-libs/gst/codecparsers/gsth264parser.c
View file

@ -84,6 +84,7 @@
# include "config.h"
#endif
#include "nalutils.h"
#include "gsth264parser.h"
#include <gst/base/gstbytereader.h>
@ -170,289 +171,6 @@ static PAR aspect_ratios[17] = {
{2, 1}
};
/* Compute Ceil(Log2(v)) */
/* Derived from branchless code for integer log2(v) from:
<http://graphics.stanford.edu/~seander/bithacks.html#IntegerLog> */
static guint
ceil_log2 (guint32 v)
{
guint r, shift;
v--;
r = (v > 0xFFFF) << 4;
v >>= r;
shift = (v > 0xFF) << 3;
v >>= shift;
r |= shift;
shift = (v > 0xF) << 2;
v >>= shift;
r |= shift;
shift = (v > 0x3) << 1;
v >>= shift;
r |= shift;
r |= (v >> 1);
return r + 1;
}
/****** Nal parser ******/
typedef struct
{
const guint8 *data;
guint size;
guint n_epb; /* Number of emulation prevention bytes */
guint byte; /* Byte position */
guint bits_in_cache; /* bitpos in the cache of next bit */
guint8 first_byte;
guint64 cache; /* cached bytes */
} NalReader;
static void
nal_reader_init (NalReader * nr, const guint8 * data, guint size)
{
nr->data = data;
nr->size = size;
nr->n_epb = 0;
nr->byte = 0;
nr->bits_in_cache = 0;
/* fill with something other than 0 to detect emulation prevention bytes */
nr->first_byte = 0xff;
nr->cache = 0xff;
}
static inline gboolean
nal_reader_read (NalReader * nr, guint nbits)
{
if (G_UNLIKELY (nr->byte * 8 + (nbits - nr->bits_in_cache) > nr->size * 8)) {
GST_DEBUG ("Can not read %u bits, bits in cache %u, Byte * 8 %u, size in "
"bits %u", nbits, nr->bits_in_cache, nr->byte * 8, nr->size * 8);
return FALSE;
}
while (nr->bits_in_cache < nbits) {
guint8 byte;
gboolean check_three_byte;
check_three_byte = TRUE;
next_byte:
if (G_UNLIKELY (nr->byte >= nr->size))
return FALSE;
byte = nr->data[nr->byte++];
/* check if the byte is a emulation_prevention_three_byte */
if (check_three_byte && byte == 0x03 && nr->first_byte == 0x00 &&
((nr->cache & 0xff) == 0)) {
/* next byte goes unconditionally to the cache, even if it's 0x03 */
check_three_byte = FALSE;
nr->n_epb++;
goto next_byte;
}
nr->cache = (nr->cache << 8) | nr->first_byte;
nr->first_byte = byte;
nr->bits_in_cache += 8;
}
return TRUE;
}
static inline gboolean
nal_reader_skip (NalReader * nr, guint nbits)
{
if (G_UNLIKELY (!nal_reader_read (nr, nbits)))
return FALSE;
nr->bits_in_cache -= nbits;
return TRUE;
}
static inline gboolean
nal_reader_skip_to_next_byte (NalReader * nr)
{
if (nr->bits_in_cache == 0) {
if (G_LIKELY ((nr->size - nr->byte) > 0))
nr->byte++;
else
return FALSE;
}
nr->bits_in_cache = 0;
return TRUE;
}
static inline guint
nal_reader_get_pos (const NalReader * nr)
{
return nr->byte * 8 - nr->bits_in_cache;
}
static inline guint
nal_reader_get_remaining (const NalReader * nr)
{
return (nr->size - nr->byte) * 8 + nr->bits_in_cache;
}
static inline guint
nal_reader_get_epb_count (const NalReader * nr)
{
return nr->n_epb;
}
#define GST_NAL_READER_READ_BITS(bits) \
static gboolean \
nal_reader_get_bits_uint##bits (NalReader *nr, guint##bits *val, guint nbits) \
{ \
guint shift; \
\
if (!nal_reader_read (nr, nbits)) \
return FALSE; \
\
/* bring the required bits down and truncate */ \
shift = nr->bits_in_cache - nbits; \
*val = nr->first_byte >> shift; \
\
*val |= nr->cache << (8 - shift); \
/* mask out required bits */ \
if (nbits < bits) \
*val &= ((guint##bits)1 << nbits) - 1; \
\
nr->bits_in_cache = shift; \
\
return TRUE; \
} \
GST_NAL_READER_READ_BITS (8);
GST_NAL_READER_READ_BITS (16);
GST_NAL_READER_READ_BITS (32);
#define GST_NAL_READER_PEAK_BITS(bits) \
static gboolean \
nal_reader_peek_bits_uint##bits (const NalReader *nr, guint##bits *val, guint nbits) \
{ \
NalReader tmp; \
\
tmp = *nr; \
return nal_reader_get_bits_uint##bits (&tmp, val, nbits); \
}
GST_NAL_READER_PEAK_BITS (8);
static gboolean
nal_reader_get_ue (NalReader * nr, guint32 * val)
{
guint i = 0;
guint8 bit;
guint32 value;
if (G_UNLIKELY (!nal_reader_get_bits_uint8 (nr, &bit, 1))) {
return FALSE;
}
while (bit == 0) {
i++;
if G_UNLIKELY
((!nal_reader_get_bits_uint8 (nr, &bit, 1)))
return FALSE;
}
if (G_UNLIKELY (i > 32))
return FALSE;
if (G_UNLIKELY (!nal_reader_get_bits_uint32 (nr, &value, i)))
return FALSE;
*val = (1 << i) - 1 + value;
return TRUE;
}
static inline gboolean
nal_reader_get_se (NalReader * nr, gint32 * val)
{
guint32 value;
if (G_UNLIKELY (!nal_reader_get_ue (nr, &value)))
return FALSE;
if (value % 2)
*val = (value / 2) + 1;
else
*val = -(value / 2);
return TRUE;
}
#define CHECK_ALLOWED(val, min, max) { \
if (val < min || val > max) { \
GST_WARNING ("value not in allowed range. value: %d, range %d-%d", \
val, min, max); \
goto error; \
} \
}
#define READ_UINT8(nr, val, nbits) { \
if (!nal_reader_get_bits_uint8 (nr, &val, nbits)) { \
GST_WARNING ("failed to read uint8, nbits: %d", nbits); \
goto error; \
} \
}
#define READ_UINT16(nr, val, nbits) { \
if (!nal_reader_get_bits_uint16 (nr, &val, nbits)) { \
GST_WARNING ("failed to read uint16, nbits: %d", nbits); \
goto error; \
} \
}
#define READ_UINT32(nr, val, nbits) { \
if (!nal_reader_get_bits_uint32 (nr, &val, nbits)) { \
GST_WARNING ("failed to read uint32, nbits: %d", nbits); \
goto error; \
} \
}
#define READ_UINT64(nr, val, nbits) { \
if (!nal_reader_get_bits_uint64 (nr, &val, nbits)) { \
GST_WARNING ("failed to read uint32, nbits: %d", nbits); \
goto error; \
} \
}
#define READ_UE(nr, val) { \
if (!nal_reader_get_ue (nr, &val)) { \
GST_WARNING ("failed to read UE"); \
goto error; \
} \
}
#define READ_UE_ALLOWED(nr, val, min, max) { \
guint32 tmp; \
READ_UE (nr, tmp); \
CHECK_ALLOWED (tmp, min, max); \
val = tmp; \
}
#define READ_SE(nr, val) { \
if (!nal_reader_get_se (nr, &val)) { \
GST_WARNING ("failed to read SE"); \
goto error; \
} \
}
#define READ_SE_ALLOWED(nr, val, min, max) { \
gint32 tmp; \
READ_SE (nr, tmp); \
CHECK_ALLOWED (tmp, min, max); \
val = tmp; \
}
/*********** end of nal parser ***************/
/***** Utils ****/
#define EXTENDED_SAR 255
@ -494,57 +212,6 @@ set_nalu_datas (GstH264NalUnit * nalu)
GST_DEBUG ("Nal type %u, ref_idc %u", nalu->type, nalu->ref_idc);
}
static inline gint
scan_for_start_codes (const guint8 * data, guint size)
{
GstByteReader br;
gst_byte_reader_init (&br, data, size);
/* NALU not empty, so we can at least expect 1 (even 2) bytes following sc */
return gst_byte_reader_masked_scan_uint32 (&br, 0xffffff00, 0x00000100,
0, size);
}
static gboolean
gst_h264_parser_byte_aligned (NalReader * nr)
{
if (nr->bits_in_cache != 0)
return FALSE;
return TRUE;
}
static gboolean
gst_h264_parser_more_data (NalReader * nr)
{
guint remaining;
remaining = nal_reader_get_remaining (nr);
if (remaining == 0)
return FALSE;
if (remaining <= 8) {
guint8 rbsp_stop_one_bit;
if (!nal_reader_peek_bits_uint8 (nr, &rbsp_stop_one_bit, 1))
return FALSE;
if (rbsp_stop_one_bit == 1) {
guint8 zero_bits;
if (remaining == 1)
return FALSE;
if (!nal_reader_peek_bits_uint8 (nr, &zero_bits, remaining))
return FALSE;
if ((zero_bits - (1 << (remaining - 1))) == 0)
return FALSE;
}
}
return TRUE;
}
/****** Parsing functions *****/
static gboolean
@ -1221,13 +888,13 @@ gst_h264_parser_parse_sei_message (GstH264NalParser * nalparser,
/* When SEI message doesn't end at byte boundary,
* check remaining bits fit the specification.
*/
if (!gst_h264_parser_byte_aligned (nr)) {
if (!gst_nal_reader_is_byte_aligned (nr)) {
guint8 bit_equal_to_one;
READ_UINT8 (nr, bit_equal_to_one, 1);
if (!bit_equal_to_one)
GST_WARNING ("Bit non equal to one.");
while (!gst_h264_parser_byte_aligned (nr)) {
while (!gst_nal_reader_is_byte_aligned (nr)) {
guint8 bit_equal_to_zero;
READ_UINT8 (nr, bit_equal_to_zero, 1);
if (bit_equal_to_zero)
@ -1791,7 +1458,7 @@ gst_h264_parse_pps (GstH264NalParser * nalparser, GstH264NalUnit * nalu,
READ_UINT8 (&nr, pps->constrained_intra_pred_flag, 1);
READ_UINT8 (&nr, pps->redundant_pic_cnt_present_flag, 1);
if (!gst_h264_parser_more_data (&nr))
if (!gst_nal_reader_has_more_data (&nr))
goto done;
READ_UINT8 (&nr, pps->transform_8x8_mode_flag, 1);
@ -2063,7 +1730,7 @@ gst_h264_parser_parse_sei (GstH264NalParser * nalparser, GstH264NalUnit * nalu,
g_array_append_val (*messages, sei);
else
break;
} while (gst_h264_parser_more_data (&nr));
} while (gst_nal_reader_has_more_data (&nr));
return res;
}

268
gst-libs/gst/codecparsers/gsth265parser.c
View file

@ -78,6 +78,7 @@
# include "config.h"
#endif
#include "nalutils.h"
#include "gsth265parser.h"
#include <gst/base/gstbytereader.h>
@ -156,262 +157,6 @@ static PAR aspect_ratios[17] = {
{2, 1}
};
/* Compute Ceil(Log2(v)) */
/* Derived from branchless code for integer log2(v) from:
<http://graphics.stanford.edu/~seander/bithacks.html#IntegerLog> */
static guint
ceil_log2 (guint32 v)
{
guint r, shift;
v--;
r = (v > 0xFFFF) << 4;
v >>= r;
shift = (v > 0xFF) << 3;
v >>= shift;
r |= shift;
shift = (v > 0xF) << 2;
v >>= shift;
r |= shift;
shift = (v > 0x3) << 1;
v >>= shift;
r |= shift;
r |= (v >> 1);
return r + 1;
}
/****** Nal parser ******/
typedef struct
{
const guint8 *data;
guint size;
guint n_epb; /* Number of emulation prevention bytes */
guint byte; /* Byte position */
guint bits_in_cache; /* bitpos in the cache of next bit */
guint8 first_byte;
guint64 cache; /* cached bytes */
} NalReader;
static void
nal_reader_init (NalReader * nr, const guint8 * data, guint size)
{
nr->data = data;
nr->size = size;
nr->n_epb = 0;
nr->byte = 0;
nr->bits_in_cache = 0;
/* fill with something other than 0 to detect emulation prevention bytes */
nr->first_byte = 0xff;
nr->cache = 0xff;
}
static inline gboolean
nal_reader_read (NalReader * nr, guint nbits)
{
if (G_UNLIKELY (nr->byte * 8 + (nbits - nr->bits_in_cache) > nr->size * 8)) {
GST_DEBUG ("Can not read %u bits, bits in cache %u, Byte * 8 %u, size in "
"bits %u", nbits, nr->bits_in_cache, nr->byte * 8, nr->size * 8);
return FALSE;
}
while (nr->bits_in_cache < nbits) {
guint8 byte;
gboolean check_three_byte;
check_three_byte = TRUE;
next_byte:
if (G_UNLIKELY (nr->byte >= nr->size))
return FALSE;
byte = nr->data[nr->byte++];
/* check if the byte is a emulation_prevention_three_byte */
if (check_three_byte && byte == 0x03 && nr->first_byte == 0x00 &&
((nr->cache & 0xff) == 0)) {
/* next byte goes unconditionally to the cache, even if it's 0x03 */
check_three_byte = FALSE;
nr->n_epb++;
goto next_byte;
}
nr->cache = (nr->cache << 8) | nr->first_byte;
nr->first_byte = byte;
nr->bits_in_cache += 8;
}
return TRUE;
}
static inline gboolean
nal_reader_skip (NalReader * nr, guint nbits)
{
if (G_UNLIKELY (!nal_reader_read (nr, nbits)))
return FALSE;
nr->bits_in_cache -= nbits;
return TRUE;
}
static inline guint
nal_reader_get_pos (const NalReader * nr)
{
return nr->byte * 8 - nr->bits_in_cache;
}
static inline guint
nal_reader_get_remaining (const NalReader * nr)
{
return (nr->size - nr->byte) * 8 + nr->bits_in_cache;
}
static inline guint
nal_reader_get_epb_count (const NalReader * nr)
{
return nr->n_epb;
}
#define GST_NAL_READER_READ_BITS(bits) \
static gboolean \
nal_reader_get_bits_uint##bits (NalReader *nr, guint##bits *val, guint nbits) \
{ \
guint shift; \
\
if (!nal_reader_read (nr, nbits)) \
return FALSE; \
\
/* bring the required bits down and truncate */ \
shift = nr->bits_in_cache - nbits; \
*val = nr->first_byte >> shift; \
\
*val |= nr->cache << (8 - shift); \
/* mask out required bits */ \
if (nbits < bits) \
*val &= ((guint##bits)1 << nbits) - 1; \
\
nr->bits_in_cache = shift; \
\
return TRUE; \
} \
GST_NAL_READER_READ_BITS (8);
GST_NAL_READER_READ_BITS (16);
GST_NAL_READER_READ_BITS (32);
static gboolean
nal_reader_get_ue (NalReader * nr, guint32 * val)
{
guint i = 0;
guint8 bit;
guint32 value;
if (G_UNLIKELY (!nal_reader_get_bits_uint8 (nr, &bit, 1))) {
return FALSE;
}
while (bit == 0) {
i++;
if G_UNLIKELY
((!nal_reader_get_bits_uint8 (nr, &bit, 1)))
return FALSE;
}
if (G_UNLIKELY (i > 32))
return FALSE;
if (G_UNLIKELY (!nal_reader_get_bits_uint32 (nr, &value, i)))
return FALSE;
*val = (1 << i) - 1 + value;
return TRUE;
}
static inline gboolean
nal_reader_get_se (NalReader * nr, gint32 * val)
{
guint32 value;
if (G_UNLIKELY (!nal_reader_get_ue (nr, &value)))
return FALSE;
if (value % 2)
*val = (value / 2) + 1;
else
*val = -(value / 2);
return TRUE;
}
#define CHECK_ALLOWED(val, min, max) { \
if (val < min || val > max) { \
GST_WARNING ("value not in allowed range. value: %d, range %d-%d", \
val, min, max); \
goto error; \
} \
}
#define READ_UINT8(nr, val, nbits) { \
if (!nal_reader_get_bits_uint8 (nr, &val, nbits)) { \
GST_WARNING ("failed to read uint8, nbits: %d", nbits); \
goto error; \
} \
}
#define READ_UINT16(nr, val, nbits) { \
if (!nal_reader_get_bits_uint16 (nr, &val, nbits)) { \
GST_WARNING ("failed to read uint16, nbits: %d", nbits); \
goto error; \
} \
}
#define READ_UINT32(nr, val, nbits) { \
if (!nal_reader_get_bits_uint32 (nr, &val, nbits)) { \
GST_WARNING ("failed to read uint32, nbits: %d", nbits); \
goto error; \
} \
}
#define READ_UINT64(nr, val, nbits) { \
if (!nal_reader_get_bits_uint64 (nr, &val, nbits)) { \
GST_WARNING ("failed to read uint32, nbits: %d", nbits); \
goto error; \
} \
}
#define READ_UE(nr, val) { \
if (!nal_reader_get_ue (nr, &val)) { \
GST_WARNING ("failed to read UE"); \
goto error; \
} \
}
#define READ_UE_ALLOWED(nr, val, min, max) { \
guint32 tmp; \
READ_UE (nr, tmp); \
CHECK_ALLOWED (tmp, min, max); \
val = tmp; \
}
#define READ_SE(nr, val) { \
if (!nal_reader_get_se (nr, &val)) { \
GST_WARNING ("failed to read SE"); \
goto error; \
} \
}
#define READ_SE_ALLOWED(nr, val, min, max) { \
gint32 tmp; \
READ_SE (nr, tmp); \
CHECK_ALLOWED (tmp, min, max); \
val = tmp; \
}
/*********** end of nal parser ***************/
/***** Utils ****/
#define EXTENDED_SAR 255
@ -476,17 +221,6 @@ gst_h265_parse_nalu_header (GstH265NalUnit * nalu)
return TRUE;
}
static inline gint
scan_for_start_codes (const guint8 * data, guint size)
{
GstByteReader br;
gst_byte_reader_init (&br, data, size);
/* NALU not empty, so we can at least expect 1 (even 2) bytes following sc */
return gst_byte_reader_masked_scan_uint32 (&br, 0xffffff00, 0x00000100,
0, size);
}
/****** Parsing functions *****/
static gboolean

296
gst-libs/gst/codecparsers/nalutils.c Normal file
View file

@ -0,0 +1,296 @@
/* Gstreamer
* Copyright (C) <2011> Intel Corporation
* Copyright (C) <2011> Collabora Ltd.
* Copyright (C) <2011> Thibault Saunier <thibault.saunier@collabora.com>
*
* Some bits C-c,C-v'ed and s/4/3 from h264parse and videoparsers/h264parse.c:
* Copyright (C) <2010> Mark Nauwelaerts <mark.nauwelaerts@collabora.co.uk>
* Copyright (C) <2010> Collabora Multimedia
* Copyright (C) <2010> Nokia Corporation
*
* (C) 2005 Michal Benes <michal.benes@itonis.tv>
* (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.
*/
/**
* Common code for NAL parsing from h264 and h265 parsers.
*/
#ifdef HAVE_CONFIG_H
# include "config.h"
#endif
#include "nalutils.h"
/* Compute Ceil(Log2(v)) */
/* Derived from branchless code for integer log2(v) from:
<http://graphics.stanford.edu/~seander/bithacks.html#IntegerLog> */
guint
ceil_log2 (guint32 v)
{
guint r, shift;
v--;
r = (v > 0xFFFF) << 4;
v >>= r;
shift = (v > 0xFF) << 3;
v >>= shift;
r |= shift;
shift = (v > 0xF) << 2;
v >>= shift;
r |= shift;
shift = (v > 0x3) << 1;
v >>= shift;
r |= shift;
r |= (v >> 1);
return r + 1;
}
/****** Nal parser ******/
void
nal_reader_init (NalReader * nr, const guint8 * data, guint size)
{
nr->data = data;
nr->size = size;
nr->n_epb = 0;
nr->byte = 0;
nr->bits_in_cache = 0;
/* fill with something other than 0 to detect emulation prevention bytes */
nr->first_byte = 0xff;
nr->cache = 0xff;
}
inline gboolean
nal_reader_read (NalReader * nr, guint nbits)
{
if (G_UNLIKELY (nr->byte * 8 + (nbits - nr->bits_in_cache) > nr->size * 8)) {
GST_DEBUG ("Can not read %u bits, bits in cache %u, Byte * 8 %u, size in "
"bits %u", nbits, nr->bits_in_cache, nr->byte * 8, nr->size * 8);
return FALSE;
}
while (nr->bits_in_cache < nbits) {
guint8 byte;
gboolean check_three_byte;
check_three_byte = TRUE;
next_byte:
if (G_UNLIKELY (nr->byte >= nr->size))
return FALSE;
byte = nr->data[nr->byte++];
/* check if the byte is a emulation_prevention_three_byte */
if (check_three_byte && byte == 0x03 && nr->first_byte == 0x00 &&
((nr->cache & 0xff) == 0)) {
/* next byte goes unconditionally to the cache, even if it's 0x03 */
check_three_byte = FALSE;
nr->n_epb++;
goto next_byte;
}
nr->cache = (nr->cache << 8) | nr->first_byte;
nr->first_byte = byte;
nr->bits_in_cache += 8;
}
return TRUE;
}
inline gboolean
nal_reader_skip (NalReader * nr, guint nbits)
{
if (G_UNLIKELY (!nal_reader_read (nr, nbits)))
return FALSE;
nr->bits_in_cache -= nbits;
return TRUE;
}
inline gboolean
nal_reader_skip_to_next_byte (NalReader * nr)
{
if (nr->bits_in_cache == 0) {
if (G_LIKELY ((nr->size - nr->byte) > 0))
nr->byte++;
else
return FALSE;
}
nr->bits_in_cache = 0;
return TRUE;
}
inline guint
nal_reader_get_pos (const NalReader * nr)
{
return nr->byte * 8 - nr->bits_in_cache;
}
inline guint
nal_reader_get_remaining (const NalReader * nr)
{
return (nr->size - nr->byte) * 8 + nr->bits_in_cache;
}
inline guint
nal_reader_get_epb_count (const NalReader * nr)
{
return nr->n_epb;
}
#define GST_NAL_READER_READ_BITS(bits) \
gboolean \
nal_reader_get_bits_uint##bits (NalReader *nr, guint##bits *val, guint nbits) \
{ \
guint shift; \
\
if (!nal_reader_read (nr, nbits)) \
return FALSE; \
\
/* bring the required bits down and truncate */ \
shift = nr->bits_in_cache - nbits; \
*val = nr->first_byte >> shift; \
\
*val |= nr->cache << (8 - shift); \
/* mask out required bits */ \
if (nbits < bits) \
*val &= ((guint##bits)1 << nbits) - 1; \
\
nr->bits_in_cache = shift; \
\
return TRUE; \
} \
GST_NAL_READER_READ_BITS (8);
GST_NAL_READER_READ_BITS (16);
GST_NAL_READER_READ_BITS (32);
#define GST_NAL_READER_PEEK_BITS(bits) \
gboolean \
nal_reader_peek_bits_uint##bits (const NalReader *nr, guint##bits *val, guint nbits) \
{ \
NalReader tmp; \
\
tmp = *nr; \
return nal_reader_get_bits_uint##bits (&tmp, val, nbits); \
}
GST_NAL_READER_PEEK_BITS (8);
gboolean
nal_reader_get_ue (NalReader * nr, guint32 * val)
{
guint i = 0;
guint8 bit;
guint32 value;
if (G_UNLIKELY (!nal_reader_get_bits_uint8 (nr, &bit, 1))) {
return FALSE;
}
while (bit == 0) {
i++;
if G_UNLIKELY
((!nal_reader_get_bits_uint8 (nr, &bit, 1)))
return FALSE;
}
if (G_UNLIKELY (i > 32))
return FALSE;
if (G_UNLIKELY (!nal_reader_get_bits_uint32 (nr, &value, i)))
return FALSE;
*val = (1 << i) - 1 + value;
return TRUE;
}
inline gboolean
nal_reader_get_se (NalReader * nr, gint32 * val)
{
guint32 value;
if (G_UNLIKELY (!nal_reader_get_ue (nr, &value)))
return FALSE;
if (value % 2)
*val = (value / 2) + 1;
else
*val = -(value / 2);
return TRUE;
}
gboolean
gst_nal_reader_is_byte_aligned (NalReader * nr)
{
if (nr->bits_in_cache != 0)
return FALSE;
return TRUE;
}
gboolean
gst_nal_reader_has_more_data (NalReader * nr)
{
guint remaining;
remaining = nal_reader_get_remaining (nr);
if (remaining == 0)
return FALSE;
if (remaining <= 8) {
guint8 rbsp_stop_one_bit;
if (!nal_reader_peek_bits_uint8 (nr, &rbsp_stop_one_bit, 1))
return FALSE;
if (rbsp_stop_one_bit == 1) {
guint8 zero_bits;
if (remaining == 1)
return FALSE;
if (!nal_reader_peek_bits_uint8 (nr, &zero_bits, remaining))
return FALSE;
if ((zero_bits - (1 << (remaining - 1))) == 0)
return FALSE;
}
}
return TRUE;
}
/*********** end of nal parser ***************/
inline gint
scan_for_start_codes (const guint8 * data, guint size)
{
GstByteReader br;
gst_byte_reader_init (&br, data, size);
/* NALU not empty, so we can at least expect 1 (even 2) bytes following sc */
return gst_byte_reader_masked_scan_uint32 (&br, 0xffffff00, 0x00000100,
0, size);
}

147
gst-libs/gst/codecparsers/nalutils.h Normal file
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@ -0,0 +1,147 @@
/* Gstreamer
* Copyright (C) <2011> Intel Corporation
* Copyright (C) <2011> Collabora Ltd.
* Copyright (C) <2011> Thibault Saunier <thibault.saunier@collabora.com>
*
* Some bits C-c,C-v'ed and s/4/3 from h264parse and videoparsers/h264parse.c:
* Copyright (C) <2010> Mark Nauwelaerts <mark.nauwelaerts@collabora.co.uk>
* Copyright (C) <2010> Collabora Multimedia
* Copyright (C) <2010> Nokia Corporation
*
* (C) 2005 Michal Benes <michal.benes@itonis.tv>
* (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.
*/
/**
* Common code for NAL parsing from h264 and h265 parsers.
*/
#ifdef HAVE_CONFIG_H
# include "config.h"
#endif
#include <gst/base/gstbytereader.h>
#include <gst/base/gstbitreader.h>
#include <string.h>
guint ceil_log2 (guint32 v);
typedef struct
{
const guint8 *data;
guint size;
guint n_epb; /* Number of emulation prevention bytes */
guint byte; /* Byte position */
guint bits_in_cache; /* bitpos in the cache of next bit */
guint8 first_byte;
guint64 cache; /* cached bytes */
} NalReader;
void nal_reader_init (NalReader * nr, const guint8 * data, guint size);
gboolean nal_reader_read (NalReader * nr, guint nbits);
gboolean nal_reader_skip (NalReader * nr, guint nbits);
gboolean nal_reader_skip_to_next_byte (NalReader * nr);
guint nal_reader_get_pos (const NalReader * nr);
guint nal_reader_get_remaining (const NalReader * nr);
guint nal_reader_get_epb_count (const NalReader * nr);
gboolean gst_nal_reader_is_byte_aligned (NalReader * nr);
gboolean gst_nal_reader_has_more_data (NalReader * nr);
#define GST_NAL_READER_READ_BITS_H(bits) \
gboolean nal_reader_get_bits_uint##bits (NalReader *nr, guint##bits *val, guint nbits)
GST_NAL_READER_READ_BITS_H (8);
GST_NAL_READER_READ_BITS_H (16);
GST_NAL_READER_READ_BITS_H (32);
#define GST_NAL_READER_PEEK_BITS_H(bits) \
gboolean nal_reader_peek_bits_uint##bits (const NalReader *nr, guint##bits *val, guint nbits)
GST_NAL_READER_PEEK_BITS_H (8);
gboolean nal_reader_get_ue (NalReader * nr, guint32 * val);
gboolean nal_reader_get_se (NalReader * nr, gint32 * val);
#define CHECK_ALLOWED(val, min, max) { \
if (val < min || val > max) { \
GST_WARNING ("value not in allowed range. value: %d, range %d-%d", \
val, min, max); \
goto error; \
} \
}
#define READ_UINT8(nr, val, nbits) { \
if (!nal_reader_get_bits_uint8 (nr, &val, nbits)) { \
GST_WARNING ("failed to read uint8, nbits: %d", nbits); \
goto error; \
} \
}
#define READ_UINT16(nr, val, nbits) { \
if (!nal_reader_get_bits_uint16 (nr, &val, nbits)) { \
GST_WARNING ("failed to read uint16, nbits: %d", nbits); \
goto error; \
} \
}
#define READ_UINT32(nr, val, nbits) { \
if (!nal_reader_get_bits_uint32 (nr, &val, nbits)) { \
GST_WARNING ("failed to read uint32, nbits: %d", nbits); \
goto error; \
} \
}
#define READ_UINT64(nr, val, nbits) { \
if (!nal_reader_get_bits_uint64 (nr, &val, nbits)) { \
GST_WARNING ("failed to read uint32, nbits: %d", nbits); \
goto error; \
} \
}
#define READ_UE(nr, val) { \
if (!nal_reader_get_ue (nr, &val)) { \
GST_WARNING ("failed to read UE"); \
goto error; \
} \
}
#define READ_UE_ALLOWED(nr, val, min, max) { \
guint32 tmp; \
READ_UE (nr, tmp); \
CHECK_ALLOWED (tmp, min, max); \
val = tmp; \
}
#define READ_SE(nr, val) { \
if (!nal_reader_get_se (nr, &val)) { \
GST_WARNING ("failed to read SE"); \
goto error; \
} \
}
#define READ_SE_ALLOWED(nr, val, min, max) { \
gint32 tmp; \
READ_SE (nr, tmp); \
CHECK_ALLOWED (tmp, min, max); \
val = tmp; \
}
gint scan_for_start_codes (const guint8 * data, guint size);