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📄 jfdct_bin_l1.c

📁 JPEG Image compression using IJG standards followed
💻 C
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/* * jfdct_bin_l1.c * * binDCT from Loeffler's algorithm: * Version L3 in the paper: 16 Shifts, 34 Adds. Coding gain: 8.8225dB. * Use floor operation for all right-shifting. * * * Reference: * J. Liang, T. D. Tran, Fast Multiplierless Approximations of the DCT with the Lifting * Scheme, IEEE Trans. Signal Processing, Vol. 49, No. 12, pp. 3032-3044, Dec. 2001.  * * Trac D. Tran and Jie Liang * ECE Department, The Johns Hopkins University * 3400 North Charles Street, 105 Barton Hall, * Baltimore, MD 21218 * E-mail: trac@jhu.edu, jieliang@jhu.edu * Dec. 2000 * - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - * Copyright (c) 2000 Trac D Tran and Jie Liang * This program is Copyright (c) by Trac D Tran and Jie Liang. * It may not be redistributed without the consent of the copyright * holders. In no circumstances may the copyright notice be removed. * The program may not be sold for profit nor may they be incorporated * in commercial programs without the written permission of the copyright * holders. This program is provided as is, without any express or * implied warranty, without even the warranty of fitness for a * particular purpose. *----------------------------------------------------------------------- * * Copyright (C) 1994-1996, Thomas G. Lane. * This file is modified from the DCT routine in the Independent JPEG Group (IJG)'s software. * For conditions of distribution and use, see the README file in IJG's package. * *//* ************************************************ * * $Log: jfdct_bin_l1.c,v $ * Revision 1.1  2000/07/23 15:37:19  jliang * Initial revision * * ************************************************ *//************************************************************************* Modification History:* Date       Programmer   Description* --------   ----------   --------------------------------------------*************************************************************************/#define JPEG_INTERNALS#include "jinclude.h"#include "jpeglib.h"#include "jdct.h"		/* Private declarations for DCT subsystem */#ifdef DCT_BIN_L1_SUPPORTED/* * This module is specialized to the case DCTSIZE = 8. */#if DCTSIZE != 8  Sorry, this code only copes with 8x8 DCTs. /* deliberate syntax err */#endif#if BITS_IN_JSAMPLE == 8#define CONST_BITS  13#define PASS1_BITS  2#else#define CONST_BITS  13#define PASS1_BITS  1		/* lose a little precision to avoid overflow */#endif/* Multiply an INT32 variable by an INT32 constant to yield an INT32 result. * For 8-bit samples with the recommended scaling, all the variable * and constant values involved are no more than 16 bits wide, so a * 16x16->32 bit multiply can be used instead of a full 32x32 multiply. * For 12-bit samples, a full 32-bit multiplication will be needed. */#if BITS_IN_JSAMPLE == 8#define MULTIPLY(var,const)  MULTIPLY16C16(var,const)#else#define MULTIPLY(var,const)  ((var) * (const))#endif//Jie 07/09/00: lossless binDCT flag, defined in cjpeg.extern boolean lossless_codec;/* * Perform the forward binDCT-A on one block of samples. * Cost: 17 shifts. */GLOBAL(void)jpeg_fdct_bin_l1 (DCTELEM * data){  INT32 tmp0, tmp1, tmp2, tmp3, tmp4, tmp5, tmp6, tmp7;  INT32 tmp10, tmp11, tmp12, tmp13;  INT32 z1;  DCTELEM *dataptr;  int ctr;  SHIFT_TEMPS	/*	fprintf(stderr, "jpeg_fdct_bin_a1 ...\n"); */  /* Pass 1: process rows. */  /* Note results are scaled up by sqrt(8) compared to a true DCT; */  /* furthermore, we scale the results by 2**PASS1_BITS. */	//fprintf(stderr, "\nOriginal image:\n");//Case 1: lossless binDCT not required. Use original butterflies.if (!lossless_codec){  dataptr = data;  for (ctr = DCTSIZE-1; ctr >= 0; ctr--) {/*******************//* Jie: test code */	//	for (tmp0 = 0; tmp0 < 8; tmp0 ++) {	//	  fprintf(stderr, "%10d", dataptr[tmp0]+128);	//	}	//	fprintf(stderr, "\n");    tmp0 = dataptr[0] + dataptr[7];    tmp7 = dataptr[0] - dataptr[7];    tmp1 = dataptr[1] + dataptr[6];    tmp6 = dataptr[1] - dataptr[6];    tmp2 = dataptr[2] + dataptr[5];    tmp5 = dataptr[2] - dataptr[5];    tmp3 = dataptr[3] + dataptr[4];    tmp4 = dataptr[3] - dataptr[4];        /* Even part */    tmp10 = (tmp0 + tmp3) ;    tmp13 = tmp0 - tmp3;    tmp11 = (tmp1 + tmp2) ;    tmp12 = tmp1 - tmp2;        dataptr[0] = (tmp10 + tmp11);         	dataptr[4] = ((dataptr[0] ) >> 1) - tmp11;	//3pi/8: 7/16, 3/8    dataptr[6] = ( ((tmp13 << 3) - tmp13 ) >> 4) - tmp12;        dataptr[2] = tmp13 - (((dataptr[6] << 1) + dataptr[6] ) >> 3);        /* Odd part */	// 3pi/16 = -1/4, 9/16, -5/16	tmp7 = tmp7 - (( tmp4 ) >> 2);	tmp4 = tmp4 + (((tmp7 << 3) + tmp7 ) >> 4);	tmp7 = tmp7 - (((tmp4 << 2) + tmp4 ) >> 4);	// pi/16 = -1/8, 3/16, -3/32	tmp6 = tmp6 - (( tmp5 ) >> 3);	tmp5 = tmp5 + (((tmp6 << 1) + tmp6 ) >> 4);	tmp6 = tmp6 - (((tmp5 << 1) + tmp5 ) >> 5);	//last group of butterflies.    dataptr[3] = tmp7 - tmp5;    dataptr[5] = tmp4 - tmp6;    tmp4 = tmp4 + tmp6;    tmp7 = tmp7 + tmp5;	dataptr[1] = tmp4 + tmp7;	dataptr[7] = ((dataptr[1] ) >> 1) - tmp4;    dataptr += DCTSIZE;		/* advance pointer to next row */  }  /* Pass 2: process columns.   * We remove the PASS1_BITS scaling, but leave the results scaled up   * by an overall factor of 8.   */  dataptr = data;  for (ctr = DCTSIZE-1; ctr >= 0; ctr--) {    tmp0 = (dataptr[DCTSIZE*0] + dataptr[DCTSIZE*7]);    tmp7 = (dataptr[DCTSIZE*0] - dataptr[DCTSIZE*7]);    tmp1 = (dataptr[DCTSIZE*1] + dataptr[DCTSIZE*6]);    tmp6 = (dataptr[DCTSIZE*1] - dataptr[DCTSIZE*6]);    tmp2 = (dataptr[DCTSIZE*2] + dataptr[DCTSIZE*5]);    tmp5 = (dataptr[DCTSIZE*2] - dataptr[DCTSIZE*5]);    tmp3 = (dataptr[DCTSIZE*3] + dataptr[DCTSIZE*4]);    tmp4 = (dataptr[DCTSIZE*3] - dataptr[DCTSIZE*4]);    /* Even part */        tmp10 = (tmp0 + tmp3);	    tmp13 = tmp0 - tmp3;    tmp11 = (tmp1 + tmp2);    tmp12 = tmp1 - tmp2;        dataptr[DCTSIZE*0] = (tmp10 + tmp11); 	dataptr[DCTSIZE*4] = ((dataptr[DCTSIZE*0] ) >> 1) - tmp11;  	// 3pi/8: 7/16, 3/8    dataptr[DCTSIZE*6] = (((tmp13 << 3) - tmp13 ) >> 4) - tmp12;    dataptr[DCTSIZE*2] = tmp13 - (((dataptr[DCTSIZE*6] << 1) + dataptr[DCTSIZE*6] ) >> 3);     /* Odd part */	// 3pi/16 = -1/4, 9/16, -5/16	tmp7 = tmp7 - (( tmp4 ) >> 2);	tmp4 = tmp4 + (((tmp7 << 3) + tmp7 ) >> 4);	tmp7 = tmp7 - (((tmp4 << 2) + tmp4 ) >> 4);	// pi/16 = -1/8, 3/16, -3/32	tmp6 = tmp6 - (( tmp5 ) >> 3);	tmp5 = tmp5 + (((tmp6 << 1) + tmp6 ) >> 4);	tmp6 = tmp6 - (((tmp5 << 1) + tmp5 ) >> 5); 	//last group of butterflies.    dataptr[DCTSIZE*3] = tmp7 - tmp5;    dataptr[DCTSIZE*5] = tmp4 - tmp6;    tmp4 = tmp4 + tmp6;    tmp7 = tmp7 + tmp5;	dataptr[DCTSIZE*1] = tmp4 + tmp7;	dataptr[DCTSIZE*7] = ((dataptr[DCTSIZE*1] ) >> 1) - tmp4;    dataptr++;			/* advance pointer to next column */  }/****************************************************************************/   } else {/****************************************************************************/  //Case 2: lossless binDCT: Use new butterflies.  dataptr = data;  for (ctr = DCTSIZE-1; ctr >= 0; ctr--) {/*******************//* Jie: test code */	//	for (tmp0 = 0; tmp0 < 8; tmp0 ++) {	//	  fprintf(stderr, "%10d", dataptr[tmp0]+128);	//	}	//	fprintf(stderr, "\n");	/*	for (z1 = 0; z1 < 8; z1 ++) {	  fprintf(stderr, "%6d", dataptr[z1]);	}	fprintf(stderr, "\n");*/    tmp7 = dataptr[0] - dataptr[7];    tmp0 = dataptr[0] - ((tmp7 ) >> 1);    tmp6 = dataptr[1] - dataptr[6];    tmp1 = dataptr[1] - ((tmp6 ) >> 1);    tmp5 = dataptr[2] - dataptr[5];    tmp2 = dataptr[2] - ((tmp5 ) >> 1);    tmp4 = dataptr[3] - dataptr[4];    tmp3 = dataptr[3] - ((tmp4 ) >> 1);       /* Even part */	//old method: larger dynamic range.	//    tmp10 = (tmp0 + tmp3) ;	/* phase 2 */	//    tmp13 = ((tmp10 ) >> 1) - tmp3;	tmp13 = tmp0 - tmp3; 	tmp10 = tmp0 - ((tmp13 ) >> 1);		//    tmp11 = (tmp1 + tmp2) ;	//    tmp12 = ((tmp11 ) >> 1) - tmp2;	tmp12 = tmp1 - tmp2;	tmp11 = tmp1 - ((tmp12 ) >> 1);       //    dataptr[0] = (tmp10 + tmp11);             /* phase 3 */	//    dataptr[4] = ((dataptr[0] ) >> 1) - tmp11;   /* Jie 05/18/00 */	dataptr[4] = tmp10 - tmp11;    dataptr[0] = tmp10 - ((dataptr[4] ) >> 1);	// 3pi/8: 7/16 and -3/8     dataptr[6] = ( ((tmp13 << 3) - tmp13 ) >> 4) - tmp12;    dataptr[2] = tmp13 - (((dataptr[6] << 1) + dataptr[6] ) >> 3);        /* Odd part */	// 3pi/16 = -1/4, 9/16, -5/16	tmp7 = tmp7 - (( tmp4 ) >> 2);	tmp4 = tmp4 + (((tmp7 << 3) + tmp7 ) >> 4);	tmp7 = tmp7 - (((tmp4 << 2) + tmp4 ) >> 4);	// pi/16 = -1/8, 3/16, -3/32	tmp6 = tmp6 - (( tmp5 ) >> 3);	tmp5 = tmp5 + (((tmp6 << 1) + tmp6 ) >> 4);	tmp6 = tmp6 - (((tmp5 << 1) + tmp5 ) >> 5);	//butterflies:	tmp6 = tmp4 - tmp6;	tmp4 = tmp4 - ((tmp6 ) >> 1);	tmp5 = tmp7 - tmp5;	tmp7 = tmp7 - ((tmp5 ) >> 1);	//last butterfly	dataptr[7] = tmp7 - tmp4;	dataptr[1] = tmp7 - ((dataptr[7] ) >> 1);    dataptr[3] = tmp5;	dataptr[5] = tmp6;    dataptr += DCTSIZE;		/* advance pointer to next row */  }  /* Pass 2: process columns.   * We remove the PASS1_BITS scaling, but leave the results scaled up   * by an overall factor of 8.   */  dataptr = data;  for (ctr = DCTSIZE-1; ctr >= 0; ctr--) {    tmp7 = dataptr[DCTSIZE*0] - dataptr[DCTSIZE*7];    tmp0 = dataptr[DCTSIZE*0] - ((tmp7 ) >> 1);    tmp6 = dataptr[DCTSIZE*1] - dataptr[DCTSIZE*6];    tmp1 = dataptr[DCTSIZE*1] - ((tmp6 ) >> 1);    tmp5 = dataptr[DCTSIZE*2] - dataptr[DCTSIZE*5];    tmp2 = dataptr[DCTSIZE*2] - ((tmp5 ) >> 1);    tmp4 = dataptr[DCTSIZE*3] - dataptr[DCTSIZE*4];    tmp3 = dataptr[DCTSIZE*3] - ((tmp4 ) >> 1);        //tmp10 = (tmp0 + tmp3);     //tmp13 = ((tmp10 ) >> 1) - tmp3;	tmp13 = tmp0 - tmp3; 	tmp10 = tmp0 - ((tmp13 ) >> 1);    //tmp11 = (tmp1 + tmp2);    //tmp12 = ((tmp11 ) >> 1) - tmp2;	tmp12 = tmp1 - tmp2;	tmp11 = tmp1 - ((tmp12 ) >> 1);	//old method: larger dynamic range    //dataptr[DCTSIZE*0] = (tmp10 + tmp11); /* phase 3 */	//dataptr[DCTSIZE*4] = ((dataptr[DCTSIZE*0] ) >> 1) - tmp11;   /* Jie 05/18/00 */	dataptr[DCTSIZE*4] = tmp10 - tmp11;    dataptr[DCTSIZE*0] = tmp10 - ((dataptr[DCTSIZE*4] ) >> 1);	// 7/16, 3/8    dataptr[DCTSIZE*6] = (((tmp13 << 3) - tmp13 ) >> 4) - tmp12;    dataptr[DCTSIZE*2] = tmp13 - (((dataptr[DCTSIZE*6] << 1) + dataptr[DCTSIZE*6] ) >> 3);     /* Odd part */	// 3pi/16 = -1/4, 9/16, -5/16	tmp7 = tmp7 - (( tmp4 ) >> 2);	tmp4 = tmp4 + (((tmp7 << 3) + tmp7 ) >> 4);	tmp7 = tmp7 - (((tmp4 << 2) + tmp4 ) >> 4);	// pi/16 = -1/8, 3/16, -3/32	tmp6 = tmp6 - (( tmp5 ) >> 3);	tmp5 = tmp5 + (((tmp6 << 1) + tmp6 ) >> 4);	tmp6 = tmp6 - (((tmp5 << 1) + tmp5 ) >> 5);	//butterflies:	tmp6 = tmp4 - tmp6;	tmp4 = tmp4 - ((tmp6 ) >> 1);	tmp5 = tmp7 - tmp5;	tmp7 = tmp7 - ((tmp5 ) >> 1);	//last butterfly	dataptr[DCTSIZE*7] = tmp7 - tmp4;	dataptr[DCTSIZE*1] = tmp7 - ((dataptr[DCTSIZE*7] ) >> 1);    dataptr[DCTSIZE*3] = tmp5;	dataptr[DCTSIZE*5] = tmp6;    dataptr++;			/* advance pointer to next column */  }} // lossless ot not. }/************************************** * problem with Sachin's code: * 1: it's verison binDCT-C. * 2: X[0] and X[4]: butterfly, not lifting. * 3: Neg scaling required. ************************************** */#endif /* DCT_BIN_L1_SUPPORTED */

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