/* * slice.c * Copyright (C) 1999-2001 Aaron Holtzman * * This file is part of mpeg2dec, a free MPEG-2 video stream decoder. * * 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 #include "mpeg2_internal.h" #include "attributes.h" /* default intra quant matrix, in zig-zag order */ static 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 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 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 header_state_init (picture_t * picture) { picture->scan = scan_norm; } int header_process_sequence_header (picture_t * picture, uint8_t * buffer) { int width, height; int i; if ((buffer[6] & 0x20) != 0x20) return 1; /* missing marker_bit */ height = (buffer[0] << 16) | (buffer[1] << 8) | buffer[2]; picture->display_picture_width = (height >> 12); picture->display_picture_height = (height & 0xfff); width = ((height >> 12) + 15) & ~15; height = ((height & 0xfff) + 15) & ~15; if ((width > 768) || (height > 576)) return 1; /* size restrictions for MP@ML or MPEG1 */ picture->coded_picture_width = width; picture->coded_picture_height = height; /* this is not used by the decoder */ picture->aspect_ratio_information = buffer[3] >> 4; picture->frame_rate_code = buffer[3] & 15; picture->bitrate = (buffer[4]<<10)|(buffer[5]<<2)|(buffer[6]>>6); if (buffer[7] & 2) { for (i = 0; i < 64; i++) picture->intra_quantizer_matrix[scan_norm[i]] = (buffer[i+7] << 7) | (buffer[i+8] >> 1); buffer += 64; } else { for (i = 0; i < 64; i++) picture->intra_quantizer_matrix[scan_norm[i]] = default_intra_quantizer_matrix [i]; } if (buffer[7] & 1) { for (i = 0; i < 64; i++) picture->non_intra_quantizer_matrix[scan_norm[i]] = buffer[i+8]; } else { for (i = 0; i < 64; i++) picture->non_intra_quantizer_matrix[i] = 16; } /* MPEG1 - for testing only */ picture->mpeg1 = 1; picture->intra_dc_precision = 0; picture->frame_pred_frame_dct = 1; picture->q_scale_type = 0; picture->concealment_motion_vectors = 0; /* picture->alternate_scan = 0; */ picture->picture_structure = FRAME_PICTURE; /* picture->second_field = 0; */ return 0; } static int header_process_sequence_extension (picture_t * picture, uint8_t * buffer) { /* check chroma format, size extensions, marker bit */ if (((buffer[1] & 0x07) != 0x02) || (buffer[2] & 0xe0) || ((buffer[3] & 0x01) != 0x01)) return 1; /* this is not used by the decoder */ picture->progressive_sequence = (buffer[1] >> 3) & 1; if (picture->progressive_sequence) picture->coded_picture_height = (picture->coded_picture_height + 31) & ~31; /* MPEG1 - for testing only */ picture->mpeg1 = 0; return 0; } static int header_process_quant_matrix_extension (picture_t * picture, uint8_t * buffer) { int i; if (buffer[0] & 8) { for (i = 0; i < 64; i++) picture->intra_quantizer_matrix[scan_norm[i]] = (buffer[i] << 5) | (buffer[i+1] >> 3); buffer += 64; } if (buffer[0] & 4) { for (i = 0; i < 64; i++) picture->non_intra_quantizer_matrix[scan_norm[i]] = (buffer[i] << 6) | (buffer[i+1] >> 2); } return 0; } static int header_process_picture_coding_extension (picture_t * picture, uint8_t * buffer) { /* pre subtract 1 for use later in compute_motion_vector */ picture->f_code[0][0] = (buffer[0] & 15) - 1; picture->f_code[0][1] = (buffer[1] >> 4) - 1; picture->f_code[1][0] = (buffer[1] & 15) - 1; picture->f_code[1][1] = (buffer[2] >> 4) - 1; picture->intra_dc_precision = (buffer[2] >> 2) & 3; picture->picture_structure = buffer[2] & 3; picture->frame_pred_frame_dct = (buffer[3] >> 6) & 1; picture->concealment_motion_vectors = (buffer[3] >> 5) & 1; picture->q_scale_type = (buffer[3] >> 4) & 1; picture->intra_vlc_format = (buffer[3] >> 3) & 1; if (buffer[3] & 4) /* alternate_scan */ picture->scan = scan_alt; else picture->scan = scan_norm; /* these are not used by the decoder */ picture->top_field_first = buffer[3] >> 7; picture->repeat_first_field = (buffer[3] >> 1) & 1; picture->progressive_frame = buffer[4] >> 7; // repeat_first implementation by A'rpi/ESP-team, based on libmpeg3: if(picture->repeat_count>=100) picture->repeat_count=0; if(picture->repeat_first_field){ if(picture->progressive_sequence){ if(picture->top_field_first) picture->repeat_count+=200; else picture->repeat_count+=100; } else if(picture->progressive_frame){ picture->repeat_count+=50; } } return 0; } int header_process_extension (picture_t * picture, uint8_t * buffer) { switch (buffer[0] & 0xf0) { case 0x10: /* sequence extension */ return header_process_sequence_extension (picture, buffer); case 0x30: /* quant matrix extension */ return header_process_quant_matrix_extension (picture, buffer); case 0x80: /* picture coding extension */ return header_process_picture_coding_extension (picture, buffer); } return 0; } int header_process_picture_header (picture_t *picture, uint8_t * buffer) { picture->picture_coding_type = (buffer [1] >> 3) & 7; /* forward_f_code and backward_f_code - used in mpeg1 only */ picture->f_code[0][1] = (buffer[3] >> 2) & 1; picture->f_code[0][0] = (((buffer[3] << 1) | (buffer[4] >> 7)) & 7) - 1; picture->f_code[1][1] = (buffer[4] >> 6) & 1; picture->f_code[1][0] = ((buffer[4] >> 3) & 7) - 1; /* move in header_process_picture_header */ picture->second_field = (picture->picture_structure != FRAME_PICTURE) && !(picture->second_field); return 0; }