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Diffstat (limited to 'gst-libs/gst/idct/fastintidct.c')
-rw-r--r-- | gst-libs/gst/idct/fastintidct.c | 215 |
1 files changed, 0 insertions, 215 deletions
diff --git a/gst-libs/gst/idct/fastintidct.c b/gst-libs/gst/idct/fastintidct.c deleted file mode 100644 index d4caaf38..00000000 --- a/gst-libs/gst/idct/fastintidct.c +++ /dev/null @@ -1,215 +0,0 @@ -/* idct.c, inverse fast discrete cosine transform */ - -/* 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. - * - */ - -/**********************************************************/ -/* 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 */ -/**********************************************************/ - -#ifdef HAVE_CONFIG_H -#include "config.h" -#endif - -/* this code assumes >> to be a two's-complement arithmetic */ -/* right shift: (-2)>>1 == -1 , (-3)>>1 == -2 */ - -#define W1 2841 /* 2048*sqrt(2)*cos(1*pi/16) */ -#define W2 2676 /* 2048*sqrt(2)*cos(2*pi/16) */ -#define W3 2408 /* 2048*sqrt(2)*cos(3*pi/16) */ -#define W5 1609 /* 2048*sqrt(2)*cos(5*pi/16) */ -#define W6 1108 /* 2048*sqrt(2)*cos(6*pi/16) */ -#define W7 565 /* 2048*sqrt(2)*cos(7*pi/16) */ - -#include "dct.h" - -/* private data */ -static short iclip[1024]; /* clipping table */ -static short *iclp; - -/* private prototypes */ -static void idctrow (short *blk); -static void idctcol (short *blk); - -/* row (horizontal) IDCT - * - * 7 pi 1 - * dst[k] = sum c[l] * src[l] * cos( -- * ( k + - ) * l ) - * l=0 8 2 - * - * where: c[0] = 128 - * c[1..7] = 128*sqrt(2) - */ - -static void -idctrow (blk) - short *blk; -{ - int x0, x1, x2, x3, x4, x5, x6, x7, x8; - - /* shortcut */ - if (!((x1 = blk[4] << 11) | (x2 = blk[6]) | (x3 = blk[2]) | - (x4 = blk[1]) | (x5 = blk[7]) | (x6 = blk[5]) | (x7 = blk[3]))) { - blk[0] = blk[1] = blk[2] = blk[3] = blk[4] = blk[5] = blk[6] = blk[7] = - blk[0] << 3; - return; - } - - x0 = (blk[0] << 11) + 128; /* for proper rounding in the fourth stage */ - - /* first stage */ - 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 */ - blk[0] = (x7 + x1) >> 8; - blk[1] = (x3 + x2) >> 8; - blk[2] = (x0 + x4) >> 8; - blk[3] = (x8 + x6) >> 8; - blk[4] = (x8 - x6) >> 8; - blk[5] = (x0 - x4) >> 8; - blk[6] = (x3 - x2) >> 8; - blk[7] = (x7 - x1) >> 8; -} - -/* column (vertical) IDCT - * - * 7 pi 1 - * dst[8*k] = sum c[l] * src[8*l] * cos( -- * ( k + - ) * l ) - * l=0 8 2 - * - * where: c[0] = 1/1024 - * c[1..7] = (1/1024)*sqrt(2) - */ -static void -idctcol (blk) - short *blk; -{ - int x0, x1, x2, x3, x4, x5, x6, x7, x8; - - /* shortcut */ - if (!((x1 = (blk[8 * 4] << 8)) | (x2 = blk[8 * 6]) | (x3 = blk[8 * 2]) | - (x4 = blk[8 * 1]) | (x5 = blk[8 * 7]) | (x6 = blk[8 * 5]) | (x7 = - blk[8 * 3]))) { - blk[8 * 0] = blk[8 * 1] = blk[8 * 2] = blk[8 * 3] = blk[8 * 4] = - blk[8 * 5] = blk[8 * 6] = blk[8 * 7] = iclp[(blk[8 * 0] + 32) >> 6]; - return; - } - - x0 = (blk[8 * 0] << 8) + 8192; - - /* first stage */ - 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 */ - blk[8 * 0] = iclp[(x7 + x1) >> 14]; - blk[8 * 1] = iclp[(x3 + x2) >> 14]; - blk[8 * 2] = iclp[(x0 + x4) >> 14]; - blk[8 * 3] = iclp[(x8 + x6) >> 14]; - blk[8 * 4] = iclp[(x8 - x6) >> 14]; - blk[8 * 5] = iclp[(x0 - x4) >> 14]; - blk[8 * 6] = iclp[(x3 - x2) >> 14]; - blk[8 * 7] = iclp[(x7 - x1) >> 14]; -} - -/* two dimensional inverse discrete cosine transform */ -void -gst_idct_fast_int_idct (block) - short *block; -{ - int i; - - for (i = 0; i < 8; i++) - idctrow (block + 8 * i); - - for (i = 0; i < 8; i++) - idctcol (block + i); -} - -void -gst_idct_init_fast_int_idct () -{ - int i; - - iclp = iclip + 512; - for (i = -512; i < 512; i++) - iclp[i] = (i < -256) ? -256 : ((i > 255) ? 255 : i); -} |