RepoMirrors
/
mpv
mirror of https://github.com/mpv-player/mpv
1
0
Fork 0
Code Issues Releases Wiki Activity
mpv/libmpeg2/header.c

692 lines
21 KiB
C
Raw Blame History

/*
* header.c
* Copyright (C) 2000-2002 Michel Lespinasse <walken@zoy.org>
* Copyright (C) 1999-2000 Aaron Holtzman <aholtzma@ess.engr.uvic.ca>
*
* This file is part of mpeg2dec, a free MPEG-2 video stream decoder.
* See http://libmpeg2.sourceforge.net/ for updates.
*
* mpeg2dec is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* mpeg2dec 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include "config.h"
#include <inttypes.h>
#include <stdlib.h> /* defines NULL */
#include <string.h> /* memcmp */
#include "mpeg2.h"
#include "mpeg2_internal.h"
#include "convert.h"
#include "attributes.h"
#define SEQ_EXT 2
#define SEQ_DISPLAY_EXT 4
#define QUANT_MATRIX_EXT 8
#define COPYRIGHT_EXT 0x10
#define PIC_DISPLAY_EXT 0x80
#define PIC_CODING_EXT 0x100
/* default intra quant matrix, in zig-zag order */
static const uint8_t default_intra_quantizer_matrix[64] ATTR_ALIGN(16) = {
8,
16, 16,
19, 16, 19,
22, 22, 22, 22,
22, 22, 26, 24, 26,
27, 27, 27, 26, 26, 26,
26, 27, 27, 27, 29, 29, 29,
34, 34, 34, 29, 29, 29, 27, 27,
29, 29, 32, 32, 34, 34, 37,
38, 37, 35, 35, 34, 35,
38, 38, 40, 40, 40,
48, 48, 46, 46,
56, 56, 58,
69, 69,
83
};
uint8_t mpeg2_scan_norm[64] ATTR_ALIGN(16) = {
/* Zig-Zag scan pattern */
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
};
uint8_t mpeg2_scan_alt[64] ATTR_ALIGN(16) = {
/* Alternate scan pattern */
0, 8, 16, 24, 1, 9, 2, 10, 17, 25, 32, 40, 48, 56, 57, 49,
41, 33, 26, 18, 3, 11, 4, 12, 19, 27, 34, 42, 50, 58, 35, 43,
51, 59, 20, 28, 5, 13, 6, 14, 21, 29, 36, 44, 52, 60, 37, 45,
53, 61, 22, 30, 7, 15, 23, 31, 38, 46, 54, 62, 39, 47, 55, 63
};
void mpeg2_header_state_init (mpeg2dec_t * mpeg2dec)
{
mpeg2dec->decoder.scan = mpeg2_scan_norm;
mpeg2dec->picture = mpeg2dec->pictures;
mpeg2dec->fbuf[0] = &mpeg2dec->fbuf_alloc[0].fbuf;
mpeg2dec->fbuf[1] = &mpeg2dec->fbuf_alloc[1].fbuf;
mpeg2dec->fbuf[2] = &mpeg2dec->fbuf_alloc[2].fbuf;
mpeg2dec->first = 1;
mpeg2dec->alloc_index = 0;
mpeg2dec->alloc_index_user = 0;
}
static void reset_info (mpeg2_info_t * info)
{
info->current_picture = info->current_picture_2nd = NULL;
info->display_picture = info->display_picture_2nd = NULL;
info->current_fbuf = info->display_fbuf = info->discard_fbuf = NULL;
info->user_data = NULL; info->user_data_len = 0;
}
int mpeg2_header_sequence (mpeg2dec_t * mpeg2dec)
{
uint8_t * buffer = mpeg2dec->chunk_start;
sequence_t * sequence = &(mpeg2dec->new_sequence);
decoder_t * decoder = &(mpeg2dec->decoder);
static unsigned int frame_period[9] = {
0, 1126125, 1125000, 1080000, 900900, 900000, 540000, 450450, 450000
};
int width, height;
int i;
if ((buffer[6] & 0x20) != 0x20) /* missing marker_bit */
return 1;
i = (buffer[0] << 16) | (buffer[1] << 8) | buffer[2];
sequence->display_width = sequence->picture_width = width = i >> 12;
sequence->display_height = sequence->picture_height = height = i & 0xfff;
decoder->width = sequence->width = width = (width + 15) & ~15;
decoder->height = sequence->height = height = (height + 15) & ~15;
decoder->vertical_position_extension = (height > 2800);
sequence->chroma_width = width >> 1;
sequence->chroma_height = height >> 1;
sequence->flags = SEQ_FLAG_PROGRESSIVE_SEQUENCE;
sequence->pixel_width = buffer[3] >> 4; /* aspect ratio */
sequence->frame_period = 0;
if ((buffer[3] & 15) < 9)
sequence->frame_period = frame_period[buffer[3] & 15];
sequence->byte_rate = (buffer[4]<<10) | (buffer[5]<<2) | (buffer[6]>>6);
sequence->vbv_buffer_size = ((buffer[6]<<16)|(buffer[7]<<8))&0x1ff800;
if (buffer[7] & 4)
sequence->flags |= SEQ_FLAG_CONSTRAINED_PARAMETERS;
if (buffer[7] & 2) {
for (i = 0; i < 64; i++)
decoder->intra_quantizer_matrix[mpeg2_scan_norm[i]] =
(buffer[i+7] << 7) | (buffer[i+8] >> 1);
buffer += 64;
} else
for (i = 0; i < 64; i++)
decoder->intra_quantizer_matrix[mpeg2_scan_norm[i]] =
default_intra_quantizer_matrix [i];
if (buffer[7] & 1)
for (i = 0; i < 64; i++)
decoder->non_intra_quantizer_matrix[mpeg2_scan_norm[i]] =
buffer[i+8];
else
for (i = 0; i < 64; i++)
decoder->non_intra_quantizer_matrix[i] = 16;
sequence->profile_level_id = 0x80;
sequence->colour_primaries = 1;
sequence->transfer_characteristics = 1;
sequence->matrix_coefficients = 1;
decoder->mpeg1 = 1;
decoder->intra_dc_precision = 0;
decoder->frame_pred_frame_dct = 1;
decoder->q_scale_type = 0;
decoder->concealment_motion_vectors = 0;
decoder->scan = mpeg2_scan_norm;
decoder->picture_structure = FRAME_PICTURE;
mpeg2dec->ext_state = SEQ_EXT;
mpeg2dec->state = STATE_SEQUENCE;
mpeg2dec->display_offset_x = mpeg2dec->display_offset_y = 0;
reset_info (&(mpeg2dec->info));
return 0;
}
static int sequence_ext (mpeg2dec_t * mpeg2dec)
{
uint8_t * buffer = mpeg2dec->chunk_start;
sequence_t * sequence = &(mpeg2dec->new_sequence);
decoder_t * decoder = &(mpeg2dec->decoder);
int width, height;
uint32_t flags;
if (!(buffer[3] & 1))
return 1;
sequence->profile_level_id = (buffer[0] << 4) | (buffer[1] >> 4);
width = sequence->display_width = sequence->picture_width +=
((buffer[1] << 13) | (buffer[2] << 5)) & 0x3000;
height = sequence->display_height = sequence->picture_height +=
(buffer[2] << 7) & 0x3000;
decoder->vertical_position_extension = (height > 2800);
flags = sequence->flags | SEQ_FLAG_MPEG2;
if (!(buffer[1] & 8)) {
flags &= ~SEQ_FLAG_PROGRESSIVE_SEQUENCE;
height = (height + 31) & ~31;
}
if (buffer[5] & 0x80)
flags |= SEQ_FLAG_LOW_DELAY;
sequence->flags = flags;
decoder->width = sequence->width = width = (width + 15) & ~15;
decoder->height = sequence->height = height = (height + 15) & ~15;
switch (buffer[1] & 6) {
case 0: /* invalid */
return 1;
case 2: /* 4:2:0 */
height >>= 1;
case 4: /* 4:2:2 */
width >>= 1;
}
sequence->chroma_width = width;
sequence->chroma_height = height;
sequence->byte_rate += ((buffer[2]<<25) | (buffer[3]<<17)) & 0x3ffc0000;
sequence->vbv_buffer_size |= buffer[4] << 21;
sequence->frame_period =
sequence->frame_period * ((buffer[5]&31)+1) / (((buffer[5]>>2)&3)+1);
decoder->mpeg1 = 0;
mpeg2dec->ext_state = SEQ_DISPLAY_EXT;
return 0;
}
static int sequence_display_ext (mpeg2dec_t * mpeg2dec)
{
uint8_t * buffer = mpeg2dec->chunk_start;
sequence_t * sequence = &(mpeg2dec->new_sequence);
uint32_t flags;
flags = ((sequence->flags & ~SEQ_MASK_VIDEO_FORMAT) |
((buffer[0]<<4) & SEQ_MASK_VIDEO_FORMAT));
if (buffer[0] & 1) {
flags |= SEQ_FLAG_COLOUR_DESCRIPTION;
sequence->colour_primaries = buffer[1];
sequence->transfer_characteristics = buffer[2];
sequence->matrix_coefficients = buffer[3];
buffer += 3;
}
if (!(buffer[2] & 2)) /* missing marker_bit */
return 1;
sequence->display_width = (buffer[1] << 6) | (buffer[2] >> 2);
sequence->display_height =
((buffer[2]& 1 ) << 13) | (buffer[3] << 5) | (buffer[4] >> 3);
return 0;
}
static inline void finalize_sequence (sequence_t * sequence)
{
int width;
int height;
sequence->byte_rate *= 50;
if (sequence->flags & SEQ_FLAG_MPEG2) {
switch (sequence->pixel_width) {
case 1: /* square pixels */
sequence->pixel_width = sequence->pixel_height = 1; return;
case 2: /* 4:3 aspect ratio */
width = 4; height = 3; break;
case 3: /* 16:9 aspect ratio */
width = 16; height = 9; break;
case 4: /* 2.21:1 aspect ratio */
width = 221; height = 100; break;
default: /* illegal */
sequence->pixel_width = sequence->pixel_height = 0; return;
}
width *= sequence->display_height;
height *= sequence->display_width;
} else {
if (sequence->byte_rate == 50 * 0x3ffff)
sequence->byte_rate = 0; /* mpeg-1 VBR */
switch (sequence->pixel_width) {
case 0: case 15: /* illegal */
sequence->pixel_width = sequence->pixel_height = 0; return;
case 1: /* square pixels */
sequence->pixel_width = sequence->pixel_height = 1; return;
case 3: /* 720x576 16:9 */
sequence->pixel_width = 64; sequence->pixel_height = 45; return;
case 6: /* 720x480 16:9 */
sequence->pixel_width = 32; sequence->pixel_height = 27; return;
case 12: /* 720*480 4:3 */
sequence->pixel_width = 8; sequence->pixel_height = 9; return;
default:
height = 88 * sequence->pixel_width + 1171;
width = 2000;
}
}
sequence->pixel_width = width;
sequence->pixel_height = height;
while (width) { /* find greatest common divisor */
int tmp = width;
width = height % tmp;
height = tmp;
}
sequence->pixel_width /= height;
sequence->pixel_height /= height;
}
void mpeg2_header_sequence_finalize (mpeg2dec_t * mpeg2dec)
{
sequence_t * sequence = &(mpeg2dec->new_sequence);
finalize_sequence (sequence);
/*
* according to 6.1.1.6, repeat sequence headers should be
* identical to the original. However some DVDs dont respect that
* and have different bitrates in the repeat sequence headers. So
* we'll ignore that in the comparison and still consider these as
* repeat sequence headers.
*/
mpeg2dec->sequence.byte_rate = sequence->byte_rate;
if (!memcmp (&(mpeg2dec->sequence), sequence, sizeof (sequence_t)))
mpeg2dec->state = STATE_SEQUENCE_REPEATED;
mpeg2dec->sequence = *sequence;
mpeg2dec->info.sequence = &(mpeg2dec->sequence);
}
int mpeg2_header_gop (mpeg2dec_t * mpeg2dec)
{
mpeg2dec->state = STATE_GOP;
reset_info (&(mpeg2dec->info));
return 0;
}
void mpeg2_set_fbuf (mpeg2dec_t * mpeg2dec, int coding_type)
{
int i;
for (i = 0; i < 3; i++)
if (mpeg2dec->fbuf[1] != &mpeg2dec->fbuf_alloc[i].fbuf &&
mpeg2dec->fbuf[2] != &mpeg2dec->fbuf_alloc[i].fbuf) {
mpeg2dec->fbuf[0] = &mpeg2dec->fbuf_alloc[i].fbuf;
mpeg2dec->info.current_fbuf = mpeg2dec->fbuf[0];
if ((coding_type == B_TYPE) ||
(mpeg2dec->sequence.flags & SEQ_FLAG_LOW_DELAY)) {
if ((coding_type == B_TYPE) || (mpeg2dec->convert_start))
mpeg2dec->info.discard_fbuf = mpeg2dec->fbuf[0];
mpeg2dec->info.display_fbuf = mpeg2dec->fbuf[0];
}
break;
}
}
int mpeg2_header_picture_start (mpeg2dec_t * mpeg2dec)
{
decoder_t * decoder = &(mpeg2dec->decoder);
picture_t * picture;
if (mpeg2dec->state != STATE_SLICE_1ST) {
mpeg2dec->state = STATE_PICTURE;
picture = mpeg2dec->pictures;
if ((decoder->coding_type != PIC_FLAG_CODING_TYPE_B) ^
(mpeg2dec->picture >= mpeg2dec->pictures + 2))
picture += 2;
} else {
mpeg2dec->state = STATE_PICTURE_2ND;
picture = mpeg2dec->picture + 1; /* second field picture */
}
mpeg2dec->picture = picture;
picture->flags = 0;
if (mpeg2dec->num_pts) {
if (mpeg2dec->bytes_since_pts >= 4) {
mpeg2dec->num_pts = 0;
picture->pts = mpeg2dec->pts_current;
picture->flags = PIC_FLAG_PTS;
} else if (mpeg2dec->num_pts > 1) {
mpeg2dec->num_pts = 1;
picture->pts = mpeg2dec->pts_previous;
picture->flags = PIC_FLAG_PTS;
}
}
picture->display_offset[0].x = picture->display_offset[1].x =
picture->display_offset[2].x = mpeg2dec->display_offset_x;
picture->display_offset[0].y = picture->display_offset[1].y =
picture->display_offset[2].y = mpeg2dec->display_offset_y;
return mpeg2_parse_header (mpeg2dec);
}
int mpeg2_header_picture (mpeg2dec_t * mpeg2dec)
{
uint8_t * buffer = mpeg2dec->chunk_start;
picture_t * picture = mpeg2dec->picture;
decoder_t * decoder = &(mpeg2dec->decoder);
int type;
int low_delay;
type = (buffer [1] >> 3) & 7;
low_delay = mpeg2dec->sequence.flags & SEQ_FLAG_LOW_DELAY;
if (mpeg2dec->state == STATE_PICTURE) {
picture_t * other;
decoder->second_field = 0;
other = mpeg2dec->pictures;
if (other == picture)
other += 2;
if (decoder->coding_type != PIC_FLAG_CODING_TYPE_B) {
mpeg2dec->fbuf[2] = mpeg2dec->fbuf[1];
mpeg2dec->fbuf[1] = mpeg2dec->fbuf[0];
}
mpeg2dec->fbuf[0] = NULL;
reset_info (&(mpeg2dec->info));
mpeg2dec->info.current_picture = picture;
mpeg2dec->info.display_picture = picture;
if (type != PIC_FLAG_CODING_TYPE_B) {
if (!low_delay) {
if (mpeg2dec->first) {
mpeg2dec->info.display_picture = NULL;
mpeg2dec->first = 0;
} else {
mpeg2dec->info.display_picture = other;
if (other->nb_fields == 1)
mpeg2dec->info.display_picture_2nd = other + 1;
mpeg2dec->info.display_fbuf = mpeg2dec->fbuf[1];
}
}
if (!low_delay + !mpeg2dec->convert_start)
mpeg2dec->info.discard_fbuf =
mpeg2dec->fbuf[!low_delay + !mpeg2dec->convert_start];
}
if (!mpeg2dec->custom_fbuf) {
while (mpeg2dec->alloc_index < 3) {
fbuf_t * fbuf;
fbuf = &(mpeg2dec->fbuf_alloc[mpeg2dec->alloc_index++].fbuf);
fbuf->id = NULL;
if (mpeg2dec->convert_start) {
fbuf->buf[0] =
(uint8_t *) mpeg2_malloc (mpeg2dec->convert_size[0],
ALLOC_CONVERTED);
fbuf->buf[1] = fbuf->buf[0] + mpeg2dec->convert_size[1];
fbuf->buf[2] = fbuf->buf[0] + mpeg2dec->convert_size[2];
} else {
int size;
size = mpeg2dec->decoder.width * mpeg2dec->decoder.height;
fbuf->buf[0] = (uint8_t *) mpeg2_malloc (6 * size >> 2,
ALLOC_YUV);
fbuf->buf[1] = fbuf->buf[0] + size;
fbuf->buf[2] = fbuf->buf[1] + (size >> 2);
}
}
mpeg2_set_fbuf (mpeg2dec, type);
}
} else {
decoder->second_field = 1;
mpeg2dec->info.current_picture_2nd = picture;
mpeg2dec->info.user_data = NULL; mpeg2dec->info.user_data_len = 0;
if (low_delay || type == PIC_FLAG_CODING_TYPE_B)
mpeg2dec->info.display_picture_2nd = picture;
}
mpeg2dec->ext_state = PIC_CODING_EXT;
picture->temporal_reference = (buffer[0] << 2) | (buffer[1] >> 6);
decoder->coding_type = type;
picture->flags |= type;
if (type == PIC_FLAG_CODING_TYPE_P || type == PIC_FLAG_CODING_TYPE_B) {
/* forward_f_code and backward_f_code - used in mpeg1 only */
decoder->f_motion.f_code[1] = (buffer[3] >> 2) & 1;
decoder->f_motion.f_code[0] =
(((buffer[3] << 1) | (buffer[4] >> 7)) & 7) - 1;
decoder->b_motion.f_code[1] = (buffer[4] >> 6) & 1;
decoder->b_motion.f_code[0] = ((buffer[4] >> 3) & 7) - 1;
}
/* XXXXXX decode extra_information_picture as well */
picture->nb_fields = 2;
return 0;
}
static int picture_coding_ext (mpeg2dec_t * mpeg2dec)
{
uint8_t * buffer = mpeg2dec->chunk_start;
picture_t * picture = mpeg2dec->picture;
decoder_t * decoder = &(mpeg2dec->decoder);
uint32_t flags;
/* pre subtract 1 for use later in compute_motion_vector */
decoder->f_motion.f_code[0] = (buffer[0] & 15) - 1;
decoder->f_motion.f_code[1] = (buffer[1] >> 4) - 1;
decoder->b_motion.f_code[0] = (buffer[1] & 15) - 1;
decoder->b_motion.f_code[1] = (buffer[2] >> 4) - 1;
flags = picture->flags;
decoder->intra_dc_precision = (buffer[2] >> 2) & 3;
decoder->picture_structure = buffer[2] & 3;
switch (decoder->picture_structure) {
case TOP_FIELD:
flags |= PIC_FLAG_TOP_FIELD_FIRST;
case BOTTOM_FIELD:
picture->nb_fields = 1;
break;
case FRAME_PICTURE:
if (!(mpeg2dec->sequence.flags & SEQ_FLAG_PROGRESSIVE_SEQUENCE)) {
picture->nb_fields = (buffer[3] & 2) ? 3 : 2;
flags |= (buffer[3] & 128) ? PIC_FLAG_TOP_FIELD_FIRST : 0;
} else
picture->nb_fields = (buffer[3]&2) ? ((buffer[3]&128) ? 6 : 4) : 2;
break;
default:
return 1;
}
decoder->top_field_first = buffer[3] >> 7;
decoder->frame_pred_frame_dct = (buffer[3] >> 6) & 1;
decoder->concealment_motion_vectors = (buffer[3] >> 5) & 1;
decoder->q_scale_type = (buffer[3] >> 4) & 1;
decoder->intra_vlc_format = (buffer[3] >> 3) & 1;
decoder->scan = (buffer[3] & 4) ? mpeg2_scan_alt : mpeg2_scan_norm;
flags |= (buffer[4] & 0x80) ? PIC_FLAG_PROGRESSIVE_FRAME : 0;
if (buffer[4] & 0x40)
flags |= (((buffer[4]<<26) | (buffer[5]<<18) | (buffer[6]<<10)) &
PIC_MASK_COMPOSITE_DISPLAY) | PIC_FLAG_COMPOSITE_DISPLAY;
picture->flags = flags;
mpeg2dec->ext_state = PIC_DISPLAY_EXT | COPYRIGHT_EXT | QUANT_MATRIX_EXT;
return 0;
}
static int picture_display_ext (mpeg2dec_t * mpeg2dec)
{
uint8_t * buffer = mpeg2dec->chunk_start;
picture_t * picture = mpeg2dec->picture;
int i, nb_pos;
nb_pos = picture->nb_fields;
if (mpeg2dec->sequence.flags & SEQ_FLAG_PROGRESSIVE_SEQUENCE)
nb_pos >>= 1;
for (i = 0; i < nb_pos; i++) {
int x, y;
x = ((buffer[4*i] << 24) | (buffer[4*i+1] << 16) |
(buffer[4*i+2] << 8) | buffer[4*i+3]) >> (11-2*i);
y = ((buffer[4*i+2] << 24) | (buffer[4*i+3] << 16) |
(buffer[4*i+4] << 8) | buffer[4*i+5]) >> (10-2*i);
if (! (x & y & 1))
return 1;
picture->display_offset[i].x = mpeg2dec->display_offset_x = x >> 1;
picture->display_offset[i].y = mpeg2dec->display_offset_y = y >> 1;
}
for (; i < 3; i++) {
picture->display_offset[i].x = mpeg2dec->display_offset_x;
picture->display_offset[i].y = mpeg2dec->display_offset_y;
}
return 0;
}
static int copyright_ext (mpeg2dec_t * mpeg2dec)
{
return 0;
}
static int quant_matrix_ext (mpeg2dec_t * mpeg2dec)
{
uint8_t * buffer = mpeg2dec->chunk_start;
decoder_t * decoder = &(mpeg2dec->decoder);
int i;
if (buffer[0] & 8) {
for (i = 0; i < 64; i++)
decoder->intra_quantizer_matrix[mpeg2_scan_norm[i]] =
(buffer[i] << 5) | (buffer[i+1] >> 3);
buffer += 64;
}
if (buffer[0] & 4)
for (i = 0; i < 64; i++)
decoder->non_intra_quantizer_matrix[mpeg2_scan_norm[i]] =
(buffer[i] << 6) | (buffer[i+1] >> 2);
return 0;
}
int mpeg2_header_extension (mpeg2dec_t * mpeg2dec)
{
static int (* parser[]) (mpeg2dec_t *) = {
0, sequence_ext, sequence_display_ext, quant_matrix_ext,
copyright_ext, 0, 0, picture_display_ext, picture_coding_ext
};
int ext, ext_bit;
ext = mpeg2dec->chunk_start[0] >> 4;
ext_bit = 1 << ext;
if (!(mpeg2dec->ext_state & ext_bit))
return 0; /* ignore illegal extensions */
mpeg2dec->ext_state &= ~ext_bit;
return parser[ext] (mpeg2dec);
}
int mpeg2_header_user_data (mpeg2dec_t * mpeg2dec)
{
if (!mpeg2dec->info.user_data_len)
mpeg2dec->info.user_data = mpeg2dec->chunk_start;
else
mpeg2dec->info.user_data_len += 3;
mpeg2dec->info.user_data_len += (mpeg2dec->chunk_ptr - 4 -
mpeg2dec->chunk_start);
mpeg2dec->chunk_start = mpeg2dec->chunk_ptr - 1;
return 0;
}
int mpeg2_header_slice_start (mpeg2dec_t * mpeg2dec)
{
mpeg2dec->state = ((mpeg2dec->picture->nb_fields > 1 ||
mpeg2dec->state == STATE_PICTURE_2ND) ?
STATE_SLICE : STATE_SLICE_1ST);
if (!(mpeg2dec->nb_decode_slices))
mpeg2dec->picture->flags |= PIC_FLAG_SKIP;
else if (mpeg2dec->convert_start) {
int flags;
switch (mpeg2dec->decoder.picture_structure) {
case TOP_FIELD: flags = CONVERT_TOP_FIELD; break;
case BOTTOM_FIELD: flags = CONVERT_BOTTOM_FIELD; break;
default:
flags =
((mpeg2dec->sequence.flags & SEQ_FLAG_PROGRESSIVE_SEQUENCE) ?
CONVERT_FRAME : CONVERT_BOTH_FIELDS);
}
mpeg2dec->convert_start (mpeg2dec->convert_id,
mpeg2dec->fbuf[0]->buf, flags);
mpeg2dec->decoder.convert = mpeg2dec->convert_copy;
mpeg2dec->decoder.fbuf_id = mpeg2dec->convert_id;
if (mpeg2dec->decoder.coding_type == B_TYPE)
mpeg2_init_fbuf (&(mpeg2dec->decoder), mpeg2dec->yuv_buf[2],
mpeg2dec->yuv_buf[mpeg2dec->yuv_index ^ 1],
mpeg2dec->yuv_buf[mpeg2dec->yuv_index]);
else {
mpeg2_init_fbuf (&(mpeg2dec->decoder),
mpeg2dec->yuv_buf[mpeg2dec->yuv_index ^ 1],
mpeg2dec->yuv_buf[mpeg2dec->yuv_index],
mpeg2dec->yuv_buf[mpeg2dec->yuv_index]);
if (mpeg2dec->state == STATE_SLICE)
mpeg2dec->yuv_index ^= 1;
}
} else {
int b_type;
//mpeg2dec->decoder.convert = NULL;
b_type = (mpeg2dec->decoder.coding_type == B_TYPE);
mpeg2_init_fbuf (&(mpeg2dec->decoder), mpeg2dec->fbuf[0]->buf,
mpeg2dec->fbuf[b_type + 1]->buf,
mpeg2dec->fbuf[b_type]->buf);
}
mpeg2dec->action = NULL;
return 0;
}
int mpeg2_header_end (mpeg2dec_t * mpeg2dec)
{
picture_t * picture;
int b_type;
picture = mpeg2dec->pictures;
if (mpeg2dec->picture < picture + 2)
picture = mpeg2dec->pictures + 2;
mpeg2dec->state = STATE_INVALID;
reset_info (&(mpeg2dec->info));
b_type = (mpeg2dec->decoder.coding_type == B_TYPE);
if (!(mpeg2dec->sequence.flags & SEQ_FLAG_LOW_DELAY)) {
mpeg2dec->info.display_picture = picture;
if (picture->nb_fields == 1)
mpeg2dec->info.display_picture_2nd = picture + 1;
mpeg2dec->info.display_fbuf = mpeg2dec->fbuf[b_type];
if (!mpeg2dec->convert_start)
mpeg2dec->info.discard_fbuf = mpeg2dec->fbuf[b_type + 1];
} else if (!mpeg2dec->convert_start)
mpeg2dec->info.discard_fbuf = mpeg2dec->fbuf[b_type];
mpeg2dec->action = mpeg2_seek_sequence;
return STATE_END;
}
Reference in New Issue View Git Blame Copy Permalink