+++ /dev/null
-/*****************************************************************************
- *
- * XVID MPEG-4 VIDEO CODEC
- * - Inverse DCT -
- *
- * These routines are from Independent JPEG Group's free JPEG software
- * Copyright (C) 1991-1998, Thomas G. Lane (see the file README.IJG)
- *
- * This program 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.
- *
- * This program 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
- *
- * $Id: idct.cpp,v 1.2 2006-12-13 15:12:27 jeanlf Exp $
- *
- ****************************************************************************/
-
-/* Copyright (C) 1996, MPEG Software Simulation Group. All Rights Reserved. */
-
-/*
- * Disclaimer of Warranty
- *
- * These software programs are available to the user without any license fee or
- * royalty on an "as is" basis. The MPEG Software Simulation Group disclaims
- * any and all warranties, whether express, implied, or statuary, including any
- * implied warranties or merchantability or of fitness for a particular
- * purpose. In no event shall the copyright-holder be liable for any
- * incidental, punitive, or consequential damages of any kind whatsoever
- * arising from the use of these programs.
- *
- * This disclaimer of warranty extends to the user of these programs and user's
- * customers, employees, agents, transferees, successors, and assigns.
- *
- * The MPEG Software Simulation Group does not represent or warrant that the
- * programs furnished hereunder are free of infringement of any third-party
- * patents.
- *
- * Commercial implementations of MPEG-1 and MPEG-2 video, including shareware,
- * are subject to royalty fees to patent holders. Many of these patents are
- * general enough such that they are unavoidable regardless of implementation
- * design.
- *
- * MPEG2AVI
- * --------
- * v0.16B33 renamed the initialization function to init_idct_int32()
- * v0.16B32 removed the unused idct_row() and idct_col() functions
- * v0.16B3 changed var declarations to static, to enforce data align
- * v0.16B22 idct_FAST() renamed to idct_int32()
- * also merged idct_FAST() into a single function, to help VC++
- * optimize it.
- *
- * v0.14 changed int to long, to avoid confusion when compiling on x86
- * platform ( in VC++ "int" -> 32bits )
- */
-
-/**********************************************************/
-/* inverse two dimensional DCT, Chen-Wang algorithm */
-/* (cf. IEEE ASSP-32, pp. 803-816, Aug. 1984) */
-/* 32-bit integer arithmetic (8 bit coefficients) */
-/* 11 mults, 29 adds per DCT */
-/* sE, 18.8.91 */
-/**********************************************************/
-/* coefficients extended to 12 bit for IEEE1180-1990 */
-/* compliance sE, 2.1.94 */
-/**********************************************************/
-
-/* this code assumes >> to be a two's-complement arithmetic */
-/* right shift: (-2)>>1 == -1 , (-3)>>1 == -2 */
-
-#include "Decoder.h"
-
-const int __W1 = 2841, //2048*sqrt(2)*cos(1*pi/16)
- __W2 = 2676, // 2048*sqrt(2)*cos(2*pi/16)
- __W3 = 2408, // 2048*sqrt(2)*cos(3*pi/16)
- __W5 = 1609, // 2048*sqrt(2)*cos(5*pi/16)
- __W6 = 1108, // 2048*sqrt(2)*cos(6*pi/16)
- __W7 = 565; // 2048*sqrt(2)*cos(7*pi/16)
-
-//----------------------------
-/* two dimensional inverse discrete cosine transform */
-//idct_int32_init() must be called before the first call to this function!
-void S_decoder::InverseDiscreteCosineTransform(int *block) const{
-
- const t_clip_val *iclp = iclip + 512;
-#if defined USE_ARM_ASM
- void InverseDiscreteCosineTransform_ARM(int *block, const int *iclip);
- InverseDiscreteCosineTransform_ARM(block, iclp);
-#else
- int i;
- //idct rows
- for(i = 8; i--; block += 8){
- int X0 = block[0];
- int X1, X2, X3, X4, X5, X6, X7;
- if(!((X1 = block[4]) | (X2 = block[6]) | (X3 = block[2]) | (X4 = block[1]) | (X5 = block[7]) | (X6 = block[5]) | (X7 = block[3]))){
- block[0] = block[1] = block[2] = block[3] = block[4] = block[5] = block[6] = block[7] = X0 << 3;
- continue;
- }
- //for proper rounding in the fourth stage
- X0 = (X0 << 11) + 128;
- X1 <<= 11;
-
- //first stage
- int X8 = __W7 * (X4 + X5);
- X4 = X8 + (__W1 - __W7) * X4;
- X5 = X8 - (__W1 + __W7) * X5;
- X8 = __W3 * (X6 + X7);
- X6 = X8 - (__W3 - __W5) * X6;
- X7 = X8 - (__W3 + __W5) * X7;
-
- //second stage
- X8 = X0 + X1;
- X0 -= X1;
- X1 = __W6 * (X3 + X2);
- X2 = X1 - (__W2 + __W6) * X2;
- X3 = X1 + (__W2 - __W6) * X3;
- X1 = X4 + X6;
- X4 -= X6;
- X6 = X5 + X7;
- X5 -= X7;
-
- //third stage
- X7 = X8 + X3;
- X8 -= X3;
- X3 = X0 + X2;
- X0 -= X2;
- X2 = (181 * (X4 + X5) + 128) >> 8;
- X4 = (181 * (X4 - X5) + 128) >> 8;
-
- //fourth stage
- block[0] = ((X7 + X1) >> 8);
- block[1] = ((X3 + X2) >> 8);
- block[2] = ((X0 + X4) >> 8);
- block[3] = ((X8 + X6) >> 8);
- block[4] = ((X8 - X6) >> 8);
- block[5] = ((X0 - X4) >> 8);
- block[6] = ((X3 - X2) >> 8);
- block[7] = ((X7 - X1) >> 8);
- }
- block -= 8*8;
- //idct columns
- for(i = 8; i--; ++block){
- int X0 = block[8 * 0];
- int X1, X2, X3, X4, X5, X6, X7;
- //shortcut
- if(!((X1 = block[8 * 4]) | (X2 = block[8 * 6]) | (X3 = block[8 * 2]) | (X4 = block[8 * 1]) | (X5 = block[8 * 7]) | (X6 = block[8 * 5]) | (X7 = block[8 * 3]))){
- block[8 * 0] = block[8 * 1] = block[8 * 2] = block[8 * 3] = block[8 * 4] = block[8 * 5] = block[8 * 6] = block[8 * 7] = iclp[(X0 + 32) >> 6];
- continue;
- }
- X0 = (X0 << 8) + 8192;
- X1 <<= 8;
-
- //first stage
- int X8 = __W7 * (X4 + X5) + 4;
- X4 = (X8 + (__W1 - __W7) * X4) >> 3;
- X5 = (X8 - (__W1 + __W7) * X5) >> 3;
- X8 = __W3 * (X6 + X7) + 4;
- X6 = (X8 - (__W3 - __W5) * X6) >> 3;
- X7 = (X8 - (__W3 + __W5) * X7) >> 3;
-
- //second stage
- X8 = X0 + X1;
- X0 -= X1;
- X1 = __W6 * (X3 + X2) + 4;
- X2 = (X1 - (__W2 + __W6) * X2) >> 3;
- X3 = (X1 + (__W2 - __W6) * X3) >> 3;
- X1 = X4 + X6;
- X4 -= X6;
- X6 = X5 + X7;
- X5 -= X7;
-
- //third stage
- X7 = X8 + X3;
- X8 -= X3;
- X3 = X0 + X2;
- X0 -= X2;
- X2 = (181 * (X4 + X5) + 128) >> 8;
- X4 = (181 * (X4 - X5) + 128) >> 8;
-
- //fourth stage
- block[8 * 0] = iclp[(X7 + X1) >> 14];
- block[8 * 1] = iclp[(X3 + X2) >> 14];
- block[8 * 2] = iclp[(X0 + X4) >> 14];
- block[8 * 3] = iclp[(X8 + X6) >> 14];
- block[8 * 4] = iclp[(X8 - X6) >> 14];
- block[8 * 5] = iclp[(X0 - X4) >> 14];
- block[8 * 6] = iclp[(X3 - X2) >> 14];
- block[8 * 7] = iclp[(X7 - X1) >> 14];
- }
-#endif
-}
-
-//----------------------------
-
-void S_decoder::idct_int32_init(){
-
- t_clip_val *iclp = iclip + 512;
- for(int i = -512; i < 512; i++)
- iclp[i] = (i < -256) ? -256 : ((i > 255) ? 255 : i);
-}
-
-//----------------------------
projects / gpac.git / commitdiff