[FFmpeg-devel] [PATCH] avcodec: Use get_ue_golomb_long() when needed
Mark Harris
mark.hsj at gmail.com
Tue Dec 29 08:04:08 CET 2015
get_ue_golomb() cannot decode values larger than 8190 (the maximum
value that can be golomb encoded in 25 bits) and produces the error
"Invalid UE golomb code" if a larger value is encountered. Use
get_ue_golomb_long() instead (which supports 63 bits, up to 4294967294)
when valid h264/hevc values can exceed 8190.
This updates decoding of the following values: (maximum)
first_mb_in_slice 36863* for level 5.2
abs_diff_pic_num_minus1 131071
difference_of_pic_nums_minus1 131071
idr_pic_id 65535
recovery_frame_cnt 65535
frame_packing_arrangement_id 4294967294
frame_packing_arrangement_repetition_period 16384
display_orientation_repetition_period 16384
An alternative would be to modify get_ue_golomb() to handle encoded
values of up to 49 bits as was done for get_se_golomb() in a92816c.
In that case get_ue_golomb() could continue to be used for all of
these except frame_packing_arrangement_id.
---
libavcodec/golomb.h | 2 +-
libavcodec/h264.c | 2 +-
libavcodec/h264_parser.c | 6 +++---
libavcodec/h264_refs.c | 4 ++--
libavcodec/h264_sei.c | 10 +++++-----
libavcodec/h264_slice.c | 2 +-
libavcodec/hevc_sei.c | 2 +-
7 files changed, 14 insertions(+), 14 deletions(-)
diff --git a/libavcodec/golomb.h b/libavcodec/golomb.h
index 5136a04..d4df0b3 100644
--- a/libavcodec/golomb.h
+++ b/libavcodec/golomb.h
@@ -48,7 +48,7 @@ extern const int8_t ff_interleaved_se_golomb_vlc_code[256];
extern const uint8_t ff_interleaved_dirac_golomb_vlc_code[256];
/**
- * read unsigned exp golomb code.
+ * Read an unsigned Exp-Golomb code in the range 0 to 8190.
*/
static inline int get_ue_golomb(GetBitContext *gb)
{
diff --git a/libavcodec/h264.c b/libavcodec/h264.c
index 089a86f..139011b 100644
--- a/libavcodec/h264.c
+++ b/libavcodec/h264.c
@@ -1365,7 +1365,7 @@ static int get_last_needed_nal(H264Context *h, const uint8_t *buf, int buf_size)
case NAL_IDR_SLICE:
case NAL_SLICE:
init_get_bits(&gb, ptr, bit_length);
- if (!get_ue_golomb(&gb) ||
+ if (!get_ue_golomb_long(&gb) || // first_mb_in_slice
!first_slice ||
first_slice != h->nal_unit_type)
nals_needed = nal_index;
diff --git a/libavcodec/h264_parser.c b/libavcodec/h264_parser.c
index 19d1aa3..12d6397 100644
--- a/libavcodec/h264_parser.c
+++ b/libavcodec/h264_parser.c
@@ -152,7 +152,7 @@ static int scan_mmco_reset(AVCodecParserContext *s)
unsigned int reordering_of_pic_nums_idc = get_ue_golomb_31(&sl->gb);
if (reordering_of_pic_nums_idc < 3)
- get_ue_golomb(&sl->gb);
+ get_ue_golomb_long(&sl->gb);
else if (reordering_of_pic_nums_idc > 3) {
av_log(h->avctx, AV_LOG_ERROR,
"illegal reordering_of_pic_nums_idc %d\n",
@@ -191,7 +191,7 @@ static int scan_mmco_reset(AVCodecParserContext *s)
return 1;
if (opcode == MMCO_SHORT2UNUSED || opcode == MMCO_SHORT2LONG)
- get_ue_golomb(&sl->gb);
+ get_ue_golomb_long(&sl->gb); // difference_of_pic_nums_minus1
if (opcode == MMCO_SHORT2LONG || opcode == MMCO_LONG2UNUSED ||
opcode == MMCO_LONG || opcode == MMCO_SET_MAX_LONG)
get_ue_golomb_31(&sl->gb);
@@ -373,7 +373,7 @@ static inline int parse_nal_units(AVCodecParserContext *s,
}
if (h->nal_unit_type == NAL_IDR_SLICE)
- get_ue_golomb(&sl->gb); /* idr_pic_id */
+ get_ue_golomb_long(&sl->gb); /* idr_pic_id */
if (h->sps.poc_type == 0) {
h->poc_lsb = get_bits(&sl->gb, h->sps.log2_max_poc_lsb);
diff --git a/libavcodec/h264_refs.c b/libavcodec/h264_refs.c
index fbdcbd6..52fedc1 100644
--- a/libavcodec/h264_refs.c
+++ b/libavcodec/h264_refs.c
@@ -266,7 +266,7 @@ int ff_h264_decode_ref_pic_list_reordering(H264Context *h, H264SliceContext *sl)
switch (modification_of_pic_nums_idc) {
case 0:
case 1: {
- const unsigned int abs_diff_pic_num = get_ue_golomb(&sl->gb) + 1;
+ const unsigned int abs_diff_pic_num = get_ue_golomb_long(&sl->gb) + 1;
int frame_num;
if (abs_diff_pic_num > h->max_pic_num) {
@@ -843,7 +843,7 @@ int ff_h264_decode_ref_pic_marking(H264Context *h, GetBitContext *gb,
mmco[i].opcode = opcode;
if (opcode == MMCO_SHORT2UNUSED || opcode == MMCO_SHORT2LONG) {
mmco[i].short_pic_num =
- (h->curr_pic_num - get_ue_golomb(gb) - 1) &
+ (h->curr_pic_num - get_ue_golomb_long(gb) - 1) &
(h->max_pic_num - 1);
#if 0
if (mmco[i].short_pic_num >= h->short_ref_count ||
diff --git a/libavcodec/h264_sei.c b/libavcodec/h264_sei.c
index 0411b87..77dd7b2 100644
--- a/libavcodec/h264_sei.c
+++ b/libavcodec/h264_sei.c
@@ -253,7 +253,7 @@ static int decode_unregistered_user_data(H264Context *h, int size)
static int decode_recovery_point(H264Context *h)
{
- h->sei_recovery_frame_cnt = get_ue_golomb(&h->gb);
+ h->sei_recovery_frame_cnt = get_ue_golomb_long(&h->gb);
/* 1b exact_match_flag,
* 1b broken_link_flag,
@@ -306,7 +306,7 @@ static int decode_buffering_period(H264Context *h)
static int decode_frame_packing_arrangement(H264Context *h)
{
- h->sei_fpa.frame_packing_arrangement_id = get_ue_golomb(&h->gb);
+ h->sei_fpa.frame_packing_arrangement_id = get_ue_golomb_long(&h->gb);
h->sei_fpa.frame_packing_arrangement_cancel_flag = get_bits1(&h->gb);
h->sei_frame_packing_present = !h->sei_fpa.frame_packing_arrangement_cancel_flag;
@@ -326,7 +326,7 @@ static int decode_frame_packing_arrangement(H264Context *h)
if (!h->quincunx_subsampling && h->frame_packing_arrangement_type != 5)
skip_bits(&h->gb, 16); // frame[01]_grid_position_[xy]
skip_bits(&h->gb, 8); // frame_packing_arrangement_reserved_byte
- h->sei_fpa.frame_packing_arrangement_repetition_period = get_ue_golomb(&h->gb) /* frame_packing_arrangement_repetition_period */;
+ h->sei_fpa.frame_packing_arrangement_repetition_period = get_ue_golomb_long(&h->gb);
}
skip_bits1(&h->gb); // frame_packing_arrangement_extension_flag
@@ -351,8 +351,8 @@ static int decode_display_orientation(H264Context *h)
h->sei_vflip = get_bits1(&h->gb); // ver_flip
h->sei_anticlockwise_rotation = get_bits(&h->gb, 16);
- get_ue_golomb(&h->gb); // display_orientation_repetition_period
- skip_bits1(&h->gb); // display_orientation_extension_flag
+ get_ue_golomb_long(&h->gb); // display_orientation_repetition_period
+ skip_bits1(&h->gb); // display_orientation_extension_flag
}
return 0;
diff --git a/libavcodec/h264_slice.c b/libavcodec/h264_slice.c
index 2db7ca2..318302f 100644
--- a/libavcodec/h264_slice.c
+++ b/libavcodec/h264_slice.c
@@ -1688,7 +1688,7 @@ int ff_h264_decode_slice_header(H264Context *h, H264SliceContext *sl)
}
if (h->nal_unit_type == NAL_IDR_SLICE)
- get_ue_golomb(&sl->gb); /* idr_pic_id */
+ get_ue_golomb_long(&sl->gb); /* idr_pic_id */
if (h->sps.poc_type == 0) {
int poc_lsb = get_bits(&sl->gb, h->sps.log2_max_poc_lsb);
diff --git a/libavcodec/hevc_sei.c b/libavcodec/hevc_sei.c
index 46cd06b..07856f2 100644
--- a/libavcodec/hevc_sei.c
+++ b/libavcodec/hevc_sei.c
@@ -82,7 +82,7 @@ static int decode_nal_sei_frame_packing_arrangement(HEVCContext *s)
{
GetBitContext *gb = &s->HEVClc->gb;
- get_ue_golomb(gb); // frame_packing_arrangement_id
+ get_ue_golomb_long(gb); // frame_packing_arrangement_id
s->sei_frame_packing_present = !get_bits1(gb);
if (s->sei_frame_packing_present) {
--
2.6.4
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