/* * slice.c * Copyright (C) 1999-2000 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 #include #include #include #include #include "config.h" #include "mpeg2.h" #include "mpeg2_internal.h" #include "header.h" // default intra quant matrix, in zig-zag order static uint8_t default_intra_quantizer_matrix[64] ALIGN_16_BYTE = { 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] ALIGN_16_BYTE = { // 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] ALIGN_16_BYTE = { // 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) { //FIXME we should set pointers to the real scan matrices here (mmx vs //normal) instead of the ifdefs in header_process_picture_coding_extension picture->scan = scan_norm; } int header_process_sequence_header (picture_t * picture, uint8_t * buffer) { unsigned int h_size; unsigned int v_size; int i; if ((buffer[6] & 0x20) != 0x20) return 1; // missing marker_bit v_size = (buffer[0] << 16) | (buffer[1] << 8) | buffer[2]; h_size = ((v_size >> 12) + 15) & ~15; v_size = ((v_size & 0xfff) + 15) & ~15; if ((h_size > 768) || (v_size > 576)) return 1; // size restrictions for MP@ML or MPEG1 //XXX this needs field fixups picture->coded_picture_width = h_size; picture->coded_picture_height = v_size; picture->last_mba = ((h_size * v_size) >> 8) - 1; // this is not used by the decoder picture->aspect_ratio_information = buffer[3] >> 4; picture->frame_rate_code = buffer[3] & 15; 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; 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; // 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) { if ((buffer[2] & 3) != 3) return 1; // not a frame picture //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->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; 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][0] = picture->f_code[0][1] = (((buffer[3] << 1) | (buffer[4] >> 7)) & 7) - 1; picture->f_code[1][0] = picture->f_code[1][1] = ((buffer[4] >> 3) & 7) - 1; return 0; }