/*
*
* This file is part of libmpeg3
*
* LibMPEG3
* Author: Adam Williams <broadcast@earthling.net>
* Page: heroine.linuxbox.com
* Page: http://www.smalltalkconsulting.com/html/mpeg3source.html (for Squeak)
*
LibMPEG3 was originally licenced under GPL. It was relicensed by
the author under the LGPL and the Squeak license on Nov 1st, 2000
This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 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
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with this library; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
Also licensed under the Squeak license.
http://www.squeak.org/license.html
*/
/* Changed Sept 15th by John M McIntosh to support Macintosh & Squeak
*/
#include "mpeg3demux.h"
#include "mpeg3private.h"
#include "mpeg3video.h"
#include <stdio.h>
#include <stdlib.h>
int mpeg3video_getseqhdr(mpeg3video_t *video)
{
int i;
mpeg3_t *file = (mpeg3_t *) video->file;
int aspect_ratio, picture_rate, vbv_buffer_size;
int constrained_parameters_flag;
int load_intra_quantizer_matrix, load_non_intra_quantizer_matrix;
video->horizontal_size = mpeg3bits_getbits(video->vstream, 12);
video->vertical_size = mpeg3bits_getbits(video->vstream, 12);
aspect_ratio = mpeg3bits_getbits(video->vstream, 4);
video->framerate_code = mpeg3bits_getbits(video->vstream, 4);
video->bitrate = mpeg3bits_getbits(video->vstream, 18);
mpeg3bits_getbit_noptr(video->vstream); /* marker bit (=1) */
vbv_buffer_size = mpeg3bits_getbits(video->vstream, 10);
constrained_parameters_flag = mpeg3bits_getbit_noptr(video->vstream);
video->frame_rate = mpeg3_frame_rate_table[video->framerate_code];
load_intra_quantizer_matrix = mpeg3bits_getbit_noptr(video->vstream);
if(load_intra_quantizer_matrix)
{
for(i = 0; i < 64; i++)
video->intra_quantizer_matrix[video->mpeg3_zigzag_scan_table[i]] = mpeg3bits_getbyte_noptr(video->vstream);
}
else
{
for(i = 0; i < 64; i++)
video->intra_quantizer_matrix[i] = mpeg3_default_intra_quantizer_matrix[i];
}
load_non_intra_quantizer_matrix = mpeg3bits_getbit_noptr(video->vstream);
if(load_non_intra_quantizer_matrix)
{
for(i = 0; i < 64; i++)
video->non_intra_quantizer_matrix[video->mpeg3_zigzag_scan_table[i]] = mpeg3bits_getbyte_noptr(video->vstream);
}
else
{
for(i = 0; i < 64; i++)
video->non_intra_quantizer_matrix[i] = 16;
}
/* copy luminance to chrominance matrices */
for(i = 0; i < 64; i++)
{
video->chroma_intra_quantizer_matrix[i] = video->intra_quantizer_matrix[i];
video->chroma_non_intra_quantizer_matrix[i] = video->non_intra_quantizer_matrix[i];
}
return 0;
}
/* decode sequence extension */
int mpeg3video_sequence_extension(mpeg3video_t *video)
{
int prof_lev;
int horizontal_size_extension, vertical_size_extension;
int bit_rate_extension, vbv_buffer_size_extension, low_delay;
int frame_rate_extension_n, frame_rate_extension_d;
int pos = 0;
video->mpeg2 = 1;
video->scalable_mode = SC_NONE; /* unless overwritten by seq. scal. ext. */
prof_lev = mpeg3bits_getbyte_noptr(video->vstream);
video->prog_seq = mpeg3bits_getbit_noptr(video->vstream);
video->chroma_format = mpeg3bits_getbits(video->vstream, 2);
horizontal_size_extension = mpeg3bits_getbits(video->vstream, 2);
vertical_size_extension = mpeg3bits_getbits(video->vstream, 2);
bit_rate_extension = mpeg3bits_getbits(video->vstream, 12);
mpeg3bits_getbit_noptr(video->vstream);
vbv_buffer_size_extension = mpeg3bits_getbyte_noptr(video->vstream);
low_delay = mpeg3bits_getbit_noptr(video->vstream);
frame_rate_extension_n = mpeg3bits_getbits(video->vstream, 2);
frame_rate_extension_d = mpeg3bits_getbits(video->vstream, 5);
video->horizontal_size = (horizontal_size_extension << 12) | (video->horizontal_size & 0x0fff);
video->vertical_size = (vertical_size_extension << 12) | (video->vertical_size & 0x0fff);
}
/* decode sequence display extension */
int mpeg3video_sequence_display_extension(mpeg3video_t *video)
{
int colour_primaries = 0, transfer_characteristics = 0;
int display_horizontal_size, display_vertical_size;
int pos = 0;
int video_format = mpeg3bits_getbits(video->vstream, 3);
int colour_description = mpeg3bits_getbit_noptr(video->vstream);
if(colour_description)
{
colour_primaries = mpeg3bits_getbyte_noptr(video->vstream);
transfer_characteristics = mpeg3bits_getbyte_noptr(video->vstream);
video->matrix_coefficients = mpeg3bits_getbyte_noptr(video->vstream);
}
display_horizontal_size = mpeg3bits_getbits(video->vstream, 14);
mpeg3bits_getbit_noptr(video->vstream);
display_vertical_size = mpeg3bits_getbits(video->vstream, 14);
}
/* decode quant matrix entension */
int mpeg3video_quant_matrix_extension(mpeg3video_t *video)
{
int i;
int load_intra_quantiser_matrix, load_non_intra_quantiser_matrix;
int load_chroma_intra_quantiser_matrix;
int load_chroma_non_intra_quantiser_matrix;
int pos = 0;
if((load_intra_quantiser_matrix = mpeg3bits_getbit_noptr(video->vstream)) != 0)
{
for(i = 0; i < 64; i++)
{
video->chroma_intra_quantizer_matrix[video->mpeg3_zigzag_scan_table[i]]
= video->intra_quantizer_matrix[video->mpeg3_zigzag_scan_table[i]]
= mpeg3bits_getbyte_noptr(video->vstream);
}
}
if((load_non_intra_quantiser_matrix = mpeg3bits_getbit_noptr(video->vstream)) != 0)
{
for (i = 0; i < 64; i++)
{
video->chroma_non_intra_quantizer_matrix[video->mpeg3_zigzag_scan_table[i]]
= video->non_intra_quantizer_matrix[video->mpeg3_zigzag_scan_table[i]]
= mpeg3bits_getbyte_noptr(video->vstream);
}
}
if((load_chroma_intra_quantiser_matrix = mpeg3bits_getbit_noptr(video->vstream)) != 0)
{
for(i = 0; i < 64; i++)
video->chroma_intra_quantizer_matrix[video->mpeg3_zigzag_scan_table[i]] = mpeg3bits_getbyte_noptr(video->vstream);
}
if((load_chroma_non_intra_quantiser_matrix = mpeg3bits_getbit_noptr(video->vstream)) != 0)
{
for(i = 0; i < 64; i++)
video->chroma_non_intra_quantizer_matrix[video->mpeg3_zigzag_scan_table[i]] = mpeg3bits_getbyte_noptr(video->vstream);
}
}
/* decode sequence scalable extension */
int mpeg3video_sequence_scalable_extension(mpeg3video_t *video)
{
int layer_id;
video->scalable_mode = mpeg3bits_getbits(video->vstream, 2) + 1; /* add 1 to make SC_DP != SC_NONE */
layer_id = mpeg3bits_getbits(video->vstream, 4);
if(video->scalable_mode == SC_SPAT)
{
video->llw = mpeg3bits_getbits(video->vstream, 14); /* lower_layer_prediction_horizontal_size */
mpeg3bits_getbit_noptr(video->vstream);
video->llh = mpeg3bits_getbits(video->vstream, 14); /* lower_layer_prediction_vertical_size */
video->hm = mpeg3bits_getbits(video->vstream, 5);
video->hn = mpeg3bits_getbits(video->vstream, 5);
video->vm = mpeg3bits_getbits(video->vstream, 5);
video->vn = mpeg3bits_getbits(video->vstream, 5);
}
if(video->scalable_mode == SC_TEMP)
fprintf(stderr, "mpeg3video_sequence_scalable_extension: temporal scalability not implemented\n");
}
/* decode picture display extension */
int mpeg3video_picture_display_extension(mpeg3video_t *video)
{
int n, i;
short frame_centre_horizontal_offset[3];
short frame_centre_vertical_offset[3];
if(video->prog_seq || video->pict_struct != FRAME_PICTURE)
n = 1;
else
n = video->repeatfirst ? 3 : 2;
for(i = 0; i < n; i++)
{
frame_centre_horizontal_offset[i] = (short)mpeg3bits_getbits(video->vstream, 16);
mpeg3bits_getbit_noptr(video->vstream);
frame_centre_vertical_offset[i] = (short)mpeg3bits_getbits(video->vstream, 16);
mpeg3bits_getbit_noptr(video->vstream);
}
}
/* decode picture coding extension */
int mpeg3video_picture_coding_extension(mpeg3video_t *video)
{
int chroma_420_type, composite_display_flag;
int v_axis = 0, field_sequence = 0, sub_carrier = 0, burst_amplitude = 0, sub_carrier_phase = 0;
video->h_forw_r_size = mpeg3bits_getbits(video->vstream, 4) - 1;
video->v_forw_r_size = mpeg3bits_getbits(video->vstream, 4) - 1;
video->h_back_r_size = mpeg3bits_getbits(video->vstream, 4) - 1;
video->v_back_r_size = mpeg3bits_getbits(video->vstream, 4) - 1;
video->dc_prec = mpeg3bits_getbits(video->vstream, 2);
video->pict_struct = mpeg3bits_getbits(video->vstream, 2);
video->topfirst = mpeg3bits_getbit_noptr(video->vstream);
video->frame_pred_dct = mpeg3bits_getbit_noptr(video->vstream);
video->conceal_mv = mpeg3bits_getbit_noptr(video->vstream);
video->qscale_type = mpeg3bits_getbit_noptr(video->vstream);
video->intravlc = mpeg3bits_getbit_noptr(video->vstream);
video->altscan = mpeg3bits_getbit_noptr(video->vstream);
video->repeatfirst = mpeg3bits_getbit_noptr(video->vstream);
chroma_420_type = mpeg3bits_getbit_noptr(video->vstream);
video->prog_frame = mpeg3bits_getbit_noptr(video->vstream);
if(video->repeat_count > 100)
video->repeat_count = 0;
video->repeat_count += 100;
video->current_repeat = 0;
if(video->prog_seq)
{
if(video->repeatfirst)
{
if(video->topfirst)
video->repeat_count += 200;
else
video->repeat_count += 100;
}
}
else
if(video->prog_frame)
{
if(video->repeatfirst)
{
video->repeat_count += 50;
}
}
/*printf("mpeg3video_picture_coding_extension %d\n", video->repeat_count); */
composite_display_flag = mpeg3bits_getbit_noptr(video->vstream);
if(composite_display_flag)
{
v_axis = mpeg3bits_getbit_noptr(video->vstream);
field_sequence = mpeg3bits_getbits(video->vstream, 3);
sub_carrier = mpeg3bits_getbit_noptr(video->vstream);
burst_amplitude = mpeg3bits_getbits(video->vstream, 7);
sub_carrier_phase = mpeg3bits_getbyte_noptr(video->vstream);
}
}
/* decode picture spatial scalable extension */
int mpeg3video_picture_spatial_scalable_extension(mpeg3video_t *video)
{
video->pict_scal = 1; /* use spatial scalability in this picture */
video->lltempref = mpeg3bits_getbits(video->vstream, 10);
mpeg3bits_getbit_noptr(video->vstream);
video->llx0 = mpeg3bits_getbits(video->vstream, 15);
if(video->llx0 >= 16384) video->llx0 -= 32768;
mpeg3bits_getbit_noptr(video->vstream);
video->lly0 = mpeg3bits_getbits(video->vstream, 15);
if(video->lly0 >= 16384) video->lly0 -= 32768;
video->stwc_table_index = mpeg3bits_getbits(video->vstream, 2);
video->llprog_frame = mpeg3bits_getbit_noptr(video->vstream);
video->llfieldsel = mpeg3bits_getbit_noptr(video->vstream);
}
/* decode picture temporal scalable extension
*
* not implemented
*
*/
int mpeg3video_picture_temporal_scalable_extension(mpeg3video_t *video)
{
fprintf(stderr, "mpeg3video_picture_temporal_scalable_extension: temporal scalability not supported\n");
}
/* decode extension and user data */
int mpeg3video_ext_user_data(mpeg3video_t *video)
{
int code = mpeg3bits_next_startcode(video->vstream);
while(code == MPEG3_EXT_START_CODE || code == MPEG3_USER_START_CODE &&
!mpeg3bits_eof(video->vstream))
{
mpeg3bits_refill(video->vstream);
if(code == MPEG3_EXT_START_CODE)
{
int ext_id = mpeg3bits_getbits(video->vstream, 4);
switch(ext_id)
{
case SEQ_ID:
mpeg3video_sequence_extension(video);
break;
case DISP_ID:
mpeg3video_sequence_display_extension(video);
break;
case QUANT_ID:
mpeg3video_quant_matrix_extension(video);
break;
case SEQSCAL_ID:
mpeg3video_sequence_scalable_extension(video);
break;
case PANSCAN_ID:
mpeg3video_picture_display_extension(video);
break;
case CODING_ID:
mpeg3video_picture_coding_extension(video);
break;
case SPATSCAL_ID:
mpeg3video_picture_spatial_scalable_extension(video);
break;
case TEMPSCAL_ID:
mpeg3video_picture_temporal_scalable_extension(video);
break;
default:
fprintf(stderr,"mpeg3video_ext_user_data: reserved extension start code ID %d\n", ext_id);
break;
}
}
code = mpeg3bits_next_startcode(video->vstream);
}
}
/* decode group of pictures header */
int mpeg3video_getgophdr(mpeg3video_t *video)
{
int drop_flag, closed_gop, broken_link;
drop_flag = mpeg3bits_getbit_noptr(video->vstream);
video->gop_timecode.hour = mpeg3bits_getbits(video->vstream, 5);
video->gop_timecode.minute = mpeg3bits_getbits(video->vstream, 6);
mpeg3bits_getbit_noptr(video->vstream);
video->gop_timecode.second = mpeg3bits_getbits(video->vstream, 6);
video->gop_timecode.frame = mpeg3bits_getbits(video->vstream, 6);
closed_gop = mpeg3bits_getbit_noptr(video->vstream);
broken_link = mpeg3bits_getbit_noptr(video->vstream);
/*
* printf("%d:%d:%d:%d %d %d %d\n", video->gop_timecode.hour, video->gop_timecode.minute, video->gop_timecode.second, video->gop_timecode.frame,
* drop_flag, closed_gop, broken_link);
*/
return mpeg3bits_error(video->vstream);
}
/* decode picture header */
int mpeg3video_getpicturehdr(mpeg3video_t *video)
{
int temp_ref, vbv_delay;
video->pict_scal = 0; /* unless overwritten by pict. spat. scal. ext. */
temp_ref = mpeg3bits_getbits(video->vstream, 10);
video->pict_type = mpeg3bits_getbits(video->vstream, 3);
vbv_delay = mpeg3bits_getbits(video->vstream, 16);
if(video->pict_type == P_TYPE || video->pict_type == B_TYPE)
{
video->full_forw = mpeg3bits_getbit_noptr(video->vstream);
video->forw_r_size = mpeg3bits_getbits(video->vstream, 3) - 1;
}
if(video->pict_type == B_TYPE)
{
video->full_back = mpeg3bits_getbit_noptr(video->vstream);
video->back_r_size = mpeg3bits_getbits(video->vstream, 3) - 1;
}
/* get extra bit picture */
while(mpeg3bits_getbit_noptr(video->vstream) &&
!mpeg3bits_eof(video->vstream)) mpeg3bits_getbyte_noptr(video->vstream);
return 0;
}
int mpeg3video_get_header(mpeg3video_t *video, int dont_repeat)
{
unsigned int code;
/* a sequence header should be found before returning from `getheader' the */
/* first time (this is to set horizontal/vertical size properly) */
/* Repeat the frame until it's less than 1 count from repeat_count */
if(video->repeat_count - video->current_repeat >= 100 && !dont_repeat)
{
return 0;
}
if(dont_repeat)
{
video->repeat_count = 0;
video->current_repeat = 0;
}
else
video->repeat_count -= video->current_repeat;
while(1)
{
/* look for startcode */
code = mpeg3bits_next_startcode(video->vstream);
if(mpeg3bits_eof(video->vstream)) return 1;
if(code != MPEG3_SEQUENCE_END_CODE) mpeg3bits_refill(video->vstream);
switch(code)
{
case MPEG3_SEQUENCE_START_CODE:
video->found_seqhdr = 1;
mpeg3video_getseqhdr(video);
mpeg3video_ext_user_data(video);
break;
case MPEG3_GOP_START_CODE:
mpeg3video_getgophdr(video);
mpeg3video_ext_user_data(video);
break;
case MPEG3_PICTURE_START_CODE:
mpeg3video_getpicturehdr(video);
mpeg3video_ext_user_data(video);
if(video->found_seqhdr) return 0; /* Exit here */
break;
case MPEG3_SEQUENCE_END_CODE:
// Continue until the end
mpeg3bits_refill(video->vstream);
break;
default:
break;
}
}
return 1; /* Shouldn't be reached. */
}
int mpeg3video_ext_bit_info(mpeg3_slice_buffer_t *slice_buffer)
{
while(mpeg3slice_getbit(slice_buffer)) mpeg3slice_getbyte(slice_buffer);
return 0;
}
/* decode slice header */
int mpeg3video_getslicehdr(mpeg3_slice_t *slice, mpeg3video_t *video)
{
int slice_vertical_position_extension, intra_slice;
int qs;
slice_vertical_position_extension = (video->mpeg2 && video->vertical_size > 2800) ?
mpeg3slice_getbits(slice->slice_buffer, 3) : 0;
if(video->scalable_mode == SC_DP) slice->pri_brk = mpeg3slice_getbits(slice->slice_buffer, 7);
qs = mpeg3slice_getbits(slice->slice_buffer, 5);
slice->quant_scale = video->mpeg2 ? (video->qscale_type ? mpeg3_non_linear_mquant_table[qs] : (qs << 1)) : qs;
if(mpeg3slice_getbit(slice->slice_buffer))
{
intra_slice = mpeg3slice_getbit(slice->slice_buffer);
mpeg3slice_getbits(slice->slice_buffer, 7);
mpeg3video_ext_bit_info(slice->slice_buffer);
}
else
intra_slice = 0;
return slice_vertical_position_extension;
}
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