Chiebot-Mirror
/
FFmpeg
mirror of https://github.com/FFmpeg/FFmpeg.git
8
0
Fork 0
Code Issues Projects Releases Wiki Activity

h264: Implement decoding of picture timing SEI message.

Browse Source 
Now correct values are propagated to interlaced_frame, top_field_first
and repeat_pict in AVFrame structure.

patch by ffdshow tryouts

Originally committed as revision 15773 to svn://svn.ffmpeg.org/ffmpeg/trunk
pull/126/head
Andreas Öman 16 years ago
parent 9f0a705d46
commit b09a7c05f6
3 changed files with 144 additions and 13 deletions
Whitespace
Show all changes Ignore whitespace when comparing lines Ignore changes in amount of whitespace Ignore changes in whitespace at EOL
Split View
Diff Options
Show Stats Download Patch File Download Diff File
  1. 121
      libavcodec/h264.c
  2. 26
      libavcodec/h264.h
  3. 4
      libavcodec/h264data.h

121
libavcodec/h264.c
Unescape View File

@ -6803,6 +6803,53 @@ static int decode_slice(struct AVCodecContext *avctx, H264Context *h){
return -1; //not reached
}
static int decode_picture_timing(H264Context *h){
MpegEncContext * const s = &h->s;
if(h->sps.nal_hrd_parameters_present_flag || h->sps.vcl_hrd_parameters_present_flag){
skip_bits(&s->gb, h->sps.cpb_removal_delay_length); /* cpb_removal_delay */
skip_bits(&s->gb, h->sps.dpb_output_delay_length); /* dpb_output_delay */
}
if(h->sps.pic_struct_present_flag){
unsigned int i, num_clock_ts;
h->sei_pic_struct = get_bits(&s->gb, 4);
if (h->sei_pic_struct > SEI_PIC_STRUCT_FRAME_TRIPLING)
return -1;
num_clock_ts = sei_num_clock_ts_table[h->sei_pic_struct];
for (i = 0 ; i < num_clock_ts ; i++){
if(get_bits(&s->gb, 1)){ /* clock_timestamp_flag */
unsigned int full_timestamp_flag;
skip_bits(&s->gb, 2); /* ct_type */
skip_bits(&s->gb, 1); /* nuit_field_based_flag */
skip_bits(&s->gb, 5); /* counting_type */
full_timestamp_flag = get_bits(&s->gb, 1);
skip_bits(&s->gb, 1); /* discontinuity_flag */
skip_bits(&s->gb, 1); /* cnt_dropped_flag */
skip_bits(&s->gb, 8); /* n_frames */
if(full_timestamp_flag){
skip_bits(&s->gb, 6); /* seconds_value 0..59 */
skip_bits(&s->gb, 6); /* minutes_value 0..59 */
skip_bits(&s->gb, 5); /* hours_value 0..23 */
}else{
if(get_bits(&s->gb, 1)){ /* seconds_flag */
skip_bits(&s->gb, 6); /* seconds_value range 0..59 */
if(get_bits(&s->gb, 1)){ /* minutes_flag */
skip_bits(&s->gb, 6); /* minutes_value 0..59 */
if(get_bits(&s->gb, 1)) /* hours_flag */
skip_bits(&s->gb, 5); /* hours_value 0..23 */
}
}
}
if(h->sps.time_offset_length > 0)
skip_bits(&s->gb, h->sps.time_offset_length); /* time_offset */
}
}
}
return 0;
}
static int decode_unregistered_user_data(H264Context *h, int size){
MpegEncContext * const s = &h->s;
uint8_t user_data[16+256];
@ -6846,6 +6893,10 @@ static int decode_sei(H264Context *h){
}while(get_bits(&s->gb, 8) == 255);
switch(type){
case 1: // Picture timing SEI
if(decode_picture_timing(h) < 0)
return -1;
break;
case 5:
if(decode_unregistered_user_data(h, size) < 0)
return -1;
@ -6873,16 +6924,15 @@ static inline void decode_hrd_parameters(H264Context *h, SPS *sps){
get_bits1(&s->gb); /* cbr_flag */
}
get_bits(&s->gb, 5); /* initial_cpb_removal_delay_length_minus1 */
get_bits(&s->gb, 5); /* cpb_removal_delay_length_minus1 */
get_bits(&s->gb, 5); /* dpb_output_delay_length_minus1 */
get_bits(&s->gb, 5); /* time_offset_length */
sps->cpb_removal_delay_length = get_bits(&s->gb, 5) + 1;
sps->dpb_output_delay_length = get_bits(&s->gb, 5) + 1;
sps->time_offset_length = get_bits(&s->gb, 5);
}
static inline int decode_vui_parameters(H264Context *h, SPS *sps){
MpegEncContext * const s = &h->s;
int aspect_ratio_info_present_flag;
unsigned int aspect_ratio_idc;
int nal_hrd_parameters_present_flag, vcl_hrd_parameters_present_flag;
aspect_ratio_info_present_flag= get_bits1(&s->gb);
@ -6929,15 +6979,15 @@ static inline int decode_vui_parameters(H264Context *h, SPS *sps){
sps->fixed_frame_rate_flag = get_bits1(&s->gb);
}
nal_hrd_parameters_present_flag = get_bits1(&s->gb);
if(nal_hrd_parameters_present_flag)
sps->nal_hrd_parameters_present_flag = get_bits1(&s->gb);
if(sps->nal_hrd_parameters_present_flag)
decode_hrd_parameters(h, sps);
vcl_hrd_parameters_present_flag = get_bits1(&s->gb);
if(vcl_hrd_parameters_present_flag)
sps->vcl_hrd_parameters_present_flag = get_bits1(&s->gb);
if(sps->vcl_hrd_parameters_present_flag)
decode_hrd_parameters(h, sps);
if(nal_hrd_parameters_present_flag || vcl_hrd_parameters_present_flag)
if(sps->nal_hrd_parameters_present_flag || sps->vcl_hrd_parameters_present_flag)
get_bits1(&s->gb); /* low_delay_hrd_flag */
get_bits1(&s->gb); /* pic_struct_present_flag */
sps->pic_struct_present_flag = get_bits1(&s->gb);
sps->bitstream_restriction_flag = get_bits1(&s->gb);
if(sps->bitstream_restriction_flag){
@ -7639,9 +7689,60 @@ static int decode_frame(AVCodecContext *avctx,
*data_size = 0;
} else {
cur->repeat_pict = 0;
/* Signal interlacing information externally. */
/* Prioritize picture timing SEI information over used decoding process if it exists. */
if(h->sps.pic_struct_present_flag){
switch (h->sei_pic_struct)
{
case SEI_PIC_STRUCT_FRAME:
cur->interlaced_frame = 0;
break;
case SEI_PIC_STRUCT_TOP_FIELD:
case SEI_PIC_STRUCT_BOTTOM_FIELD:
case SEI_PIC_STRUCT_TOP_BOTTOM:
case SEI_PIC_STRUCT_BOTTOM_TOP:
cur->interlaced_frame = 1;
break;
case SEI_PIC_STRUCT_TOP_BOTTOM_TOP:
case SEI_PIC_STRUCT_BOTTOM_TOP_BOTTOM:
// Signal the possibility of telecined film externally (pic_struct 5,6)
// From these hints, let the applications decide if they apply deinterlacing.
cur->repeat_pict = 1;
cur->interlaced_frame = FIELD_OR_MBAFF_PICTURE;
break;
case SEI_PIC_STRUCT_FRAME_DOUBLING:
// Force progressive here, as doubling interlaced frame is a bad idea.
cur->interlaced_frame = 0;
cur->repeat_pict = 2;
break;
case SEI_PIC_STRUCT_FRAME_TRIPLING:
cur->interlaced_frame = 0;
cur->repeat_pict = 4;
break;
}
}else{
/* Derive interlacing flag from used decoding process. */
cur->interlaced_frame = FIELD_OR_MBAFF_PICTURE;
}
if (cur->field_poc[0] != cur->field_poc[1]){
/* Derive top_field_first from field pocs. */
cur->top_field_first = cur->field_poc[0] < cur->field_poc[1];
}else{
if(cur->interlaced_frame || h->sps.pic_struct_present_flag){
/* Use picture timing SEI information. Even if it is a information of a past frame, better than nothing. */
if(h->sei_pic_struct == SEI_PIC_STRUCT_TOP_BOTTOM
|| h->sei_pic_struct == SEI_PIC_STRUCT_TOP_BOTTOM_TOP)
cur->top_field_first = 1;
else
cur->top_field_first = 0;
}else{
/* Most likely progressive */
cur->top_field_first = 0;
}
}
//FIXME do something with unavailable reference frames

26
libavcodec/h264.h
Unescape View File

@ -110,6 +110,21 @@ enum {
NAL_AUXILIARY_SLICE=19
};
/**
* pic_struct in picture timing SEI message
*/
typedef enum {
SEI_PIC_STRUCT_FRAME = 0, ///< 0: %frame
SEI_PIC_STRUCT_TOP_FIELD = 1, ///< 1: top field
SEI_PIC_STRUCT_BOTTOM_FIELD = 2, ///< 2: bottom field
SEI_PIC_STRUCT_TOP_BOTTOM = 3, ///< 3: top field, bottom field, in that order
SEI_PIC_STRUCT_BOTTOM_TOP = 4, ///< 4: bottom field, top field, in that order
SEI_PIC_STRUCT_TOP_BOTTOM_TOP = 5, ///< 5: top field, bottom field, top field repeated, in that order
SEI_PIC_STRUCT_BOTTOM_TOP_BOTTOM = 6, ///< 6: bottom field, top field, bottom field repeated, in that order
SEI_PIC_STRUCT_FRAME_DOUBLING = 7, ///< 7: %frame doubling
SEI_PIC_STRUCT_FRAME_TRIPLING = 8 ///< 8: %frame tripling
} SEI_PicStructType;
/**
* Sequence parameter set
*/
@ -150,6 +165,12 @@ typedef struct SPS{
int scaling_matrix_present;
uint8_t scaling_matrix4[6][16];
uint8_t scaling_matrix8[2][64];
int nal_hrd_parameters_present_flag;
int vcl_hrd_parameters_present_flag;
int pic_struct_present_flag;
int time_offset_length;
int cpb_removal_delay_length; ///< cpb_removal_delay_length_minus1 + 1
int dpb_output_delay_length; ///< dpb_output_delay_length_minus1 + 1
}SPS;
/**
@ -460,6 +481,11 @@ typedef struct H264Context{
int mb_xy;
uint32_t svq3_watermark_key;
/**
* pic_struct in picture timing SEI message
*/
SEI_PicStructType sei_pic_struct;
}H264Context;
#endif /* AVCODEC_H264_H */

4
libavcodec/h264data.h
Unescape View File

@ -1296,4 +1296,8 @@ static const int8_t cabac_context_init_PB[3][460][2] =
}
};
static const uint8_t sei_num_clock_ts_table[9]={
1, 1, 1, 2, 2, 3, 3, 2, 3
};
#endif /* AVCODEC_H264DATA_H */

Write Preview
Loading…
Cancel
Save