diff options
Diffstat (limited to 'src/libmpeg2new/libmpeg2/header.c')
| -rw-r--r-- | src/libmpeg2new/libmpeg2/header.c | 725 |
1 files changed, 725 insertions, 0 deletions
diff --git a/src/libmpeg2new/libmpeg2/header.c b/src/libmpeg2new/libmpeg2/header.c new file mode 100644 index 000000000..55f16f1ee --- /dev/null +++ b/src/libmpeg2new/libmpeg2/header.c @@ -0,0 +1,725 @@ +/* + * header.c + * Copyright (C) 2000-2003 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; + mpeg2_sequence_t * sequence = &(mpeg2dec->new_sequence); + static unsigned int frame_period[9] = { + 0, 1126125, 1125000, 1080000, 900900, 900000, 540000, 450450, 450000 + }; + int i; + + if ((buffer[6] & 0x20) != 0x20) /* missing marker_bit */ + return 1; + + i = (buffer[0] << 16) | (buffer[1] << 8) | buffer[2]; + if (! (sequence->display_width = sequence->picture_width = i >> 12)) + return 1; + if (! (sequence->display_height = sequence->picture_height = i & 0xfff)) + return 1; + sequence->width = (sequence->picture_width + 15) & ~15; + sequence->height = (sequence->picture_height + 15) & ~15; + sequence->chroma_width = sequence->width >> 1; + sequence->chroma_height = sequence->height >> 1; + + sequence->flags = (SEQ_FLAG_PROGRESSIVE_SEQUENCE | + SEQ_VIDEO_FORMAT_UNSPECIFIED); + + 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; + + mpeg2dec->copy_matrix = 3; + if (buffer[7] & 2) { + for (i = 0; i < 64; i++) + mpeg2dec->intra_quantizer_matrix[mpeg2_scan_norm[i]] = + (buffer[i+7] << 7) | (buffer[i+8] >> 1); + buffer += 64; + } else + for (i = 0; i < 64; i++) + mpeg2dec->intra_quantizer_matrix[mpeg2_scan_norm[i]] = + default_intra_quantizer_matrix[i]; + + if (buffer[7] & 1) + for (i = 0; i < 64; i++) + mpeg2dec->non_intra_quantizer_matrix[mpeg2_scan_norm[i]] = + buffer[i+8]; + else + for (i = 0; i < 64; i++) + mpeg2dec->non_intra_quantizer_matrix[i] = 16; + + sequence->profile_level_id = 0x80; + sequence->colour_primaries = 0; + sequence->transfer_characteristics = 0; + sequence->matrix_coefficients = 0; + + mpeg2dec->ext_state = SEQ_EXT; + mpeg2dec->state = STATE_SEQUENCE; + mpeg2dec->display_offset_x = mpeg2dec->display_offset_y = 0; + + reset_info (&(mpeg2dec->info)); + mpeg2dec->info.gop = NULL; + return 0; +} + +static int sequence_ext (mpeg2dec_t * mpeg2dec) +{ + uint8_t * buffer = mpeg2dec->chunk_start; + mpeg2_sequence_t * sequence = &(mpeg2dec->new_sequence); + uint32_t flags; + + if (!(buffer[3] & 1)) + return 1; + + sequence->profile_level_id = (buffer[0] << 4) | (buffer[1] >> 4); + + sequence->display_width = sequence->picture_width += + ((buffer[1] << 13) | (buffer[2] << 5)) & 0x3000; + sequence->display_height = sequence->picture_height += + (buffer[2] << 7) & 0x3000; + sequence->width = (sequence->picture_width + 15) & ~15; + sequence->height = (sequence->picture_height + 15) & ~15; + flags = sequence->flags | SEQ_FLAG_MPEG2; + if (!(buffer[1] & 8)) { + flags &= ~SEQ_FLAG_PROGRESSIVE_SEQUENCE; + sequence->height = (sequence->height + 31) & ~31; + } + if (buffer[5] & 0x80) + flags |= SEQ_FLAG_LOW_DELAY; + sequence->flags = flags; + sequence->chroma_width = sequence->width; + sequence->chroma_height = sequence->height; + switch (buffer[1] & 6) { + case 0: /* invalid */ + return 1; + case 2: /* 4:2:0 */ + sequence->chroma_height >>= 1; + case 4: /* 4:2:2 */ + sequence->chroma_width >>= 1; + } + + 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); + + mpeg2dec->ext_state = SEQ_DISPLAY_EXT; + + return 0; +} + +static int sequence_display_ext (mpeg2dec_t * mpeg2dec) +{ + uint8_t * buffer = mpeg2dec->chunk_start; + mpeg2_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 (mpeg2_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_matrix_finalize (mpeg2dec_t * mpeg2dec) +{ + mpeg2_decoder_t * decoder = &(mpeg2dec->decoder); + int i; + + if (mpeg2dec->copy_matrix & 1) + for (i = 0; i < 64; i++) + decoder->intra_quantizer_matrix[i] = + mpeg2dec->intra_quantizer_matrix[i]; + if (mpeg2dec->copy_matrix & 2) + for (i = 0; i < 64; i++) + decoder->non_intra_quantizer_matrix[i] = + mpeg2dec->non_intra_quantizer_matrix[i]; +} + +void mpeg2_header_sequence_finalize (mpeg2dec_t * mpeg2dec) +{ + mpeg2_sequence_t * sequence = &(mpeg2dec->new_sequence); + mpeg2_decoder_t * decoder = &(mpeg2dec->decoder); + + finalize_sequence (sequence); + + mpeg2_header_matrix_finalize (mpeg2dec); + decoder->mpeg1 = !(sequence->flags & SEQ_FLAG_MPEG2); + decoder->width = sequence->width; + decoder->height = sequence->height; + decoder->vertical_position_extension = (sequence->picture_height > 2800); + + /* + * 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 (mpeg2_sequence_t))) + mpeg2dec->state = STATE_SEQUENCE_REPEATED; + mpeg2dec->sequence = *sequence; + + mpeg2dec->info.sequence = &(mpeg2dec->sequence); +} + +int mpeg2_header_gop (mpeg2dec_t * mpeg2dec) +{ + uint8_t * buffer = mpeg2dec->chunk_start; + mpeg2_gop_t * gop = &(mpeg2dec->gop); + + reset_info (&(mpeg2dec->info)); + if (! (buffer[1] & 8)) + return 1; + mpeg2dec->info.gop = gop; + gop->hours = (buffer[0] >> 2) & 31; + gop->minutes = ((buffer[0] << 4) | (buffer[1] >> 4)) & 63; + gop->seconds = ((buffer[1] << 3) | (buffer[2] >> 5)) & 63; + gop->pictures = ((buffer[2] << 1) | (buffer[3] >> 7)) & 63; + gop->flags = (buffer[0] >> 7) | ((buffer[3] >> 4) & 6); + mpeg2dec->state = STATE_GOP; + 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; + } +} + +mpeg2_state_t mpeg2_header_picture_start (mpeg2dec_t * mpeg2dec) +{ + mpeg2_decoder_t * decoder = &(mpeg2dec->decoder); + mpeg2_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; + mpeg2_picture_t * picture = mpeg2dec->picture; + mpeg2_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) { + mpeg2_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) { + mpeg2_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; + + 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->copy_matrix = 0; + + return 0; +} + +static int picture_coding_ext (mpeg2dec_t * mpeg2dec) +{ + uint8_t * buffer = mpeg2dec->chunk_start; + mpeg2_picture_t * picture = mpeg2dec->picture; + mpeg2_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; + mpeg2_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; + int i; + + if (buffer[0] & 8) { + for (i = 0; i < 64; i++) + mpeg2dec->intra_quantizer_matrix[mpeg2_scan_norm[i]] = + (buffer[i] << 5) | (buffer[i+1] >> 3); + mpeg2dec->copy_matrix |= 1; + buffer += 64; + } + + if (buffer[0] & 4) { + for (i = 0; i < 64; i++) + mpeg2dec->non_intra_quantizer_matrix[mpeg2_scan_norm[i]] = + (buffer[i] << 6) | (buffer[i+1] >> 2); + mpeg2dec->copy_matrix |= 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; +} + +mpeg2_state_t mpeg2_header_slice_start (mpeg2dec_t * mpeg2dec) +{ + mpeg2dec->info.user_data = NULL; mpeg2dec->info.user_data_len = 0; + 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 (mpeg2_state_t)-1; +} + +mpeg2_state_t mpeg2_header_end (mpeg2dec_t * mpeg2dec) +{ + mpeg2_picture_t * picture; + int b_type; + + b_type = (mpeg2dec->decoder.coding_type == B_TYPE); + picture = mpeg2dec->pictures; + if ((mpeg2dec->picture >= picture + 2) ^ b_type) + picture = mpeg2dec->pictures + 2; + + mpeg2dec->state = STATE_END; + reset_info (&(mpeg2dec->info)); + 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; + mpeg2dec->first = 1; + return STATE_END; +} |