/*===========================================================================* * bframe.c * * * * Procedures concerned with the B-frame encoding * * * * EXPORTED PROCEDURES: * * GenBFrame * * ResetBFrameStats * * ShowBFrameSummary * * EstimateSecondsPerBFrame * * ComputeBMotionLumBlock * * SetBQScale * * GetBQScale * * * *===========================================================================*/ /* * Copyright (c) 1993 The Regents of the University of California. * All rights reserved. * * Permission to use, copy, modify, and distribute this software and its * documentation for any purpose, without fee, and without written agreement is * hereby granted, provided that the above copyright notice and the following * two paragraphs appear in all copies of this software. * * IN NO EVENT SHALL THE UNIVERSITY OF CALIFORNIA BE LIABLE TO ANY PARTY FOR * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES ARISING OUT * OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN IF THE UNIVERSITY OF * CALIFORNIA HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. * * THE UNIVERSITY OF CALIFORNIA SPECIFICALLY DISCLAIMS ANY WARRANTIES, * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY * AND FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS * ON AN "AS IS" BASIS, AND THE UNIVERSITY OF CALIFORNIA HAS NO OBLIGATION TO * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS. */ /* * $Header: /home/daf/mpeg/mpgwrite/RCS/bframe.c,v 1.4 1994/01/11 22:54:23 daf Exp $ * $Log: bframe.c,v $ * Revision 1.4 1994/01/11 22:54:23 daf * Modified for PC compatibility * * Revision 1.3 1994/01/11 21:45:06 daf * Modified for PC compatibility * * Revision 1.2 1994/01/07 17:28:26 daf * Modified for use as .mex file. * * Revision 1.5 1993/07/30 19:24:04 keving * nothing * * Revision 1.4 1993/07/22 22:23:43 keving * nothing * * Revision 1.3 1993/06/30 20:06:09 keving * nothing * * Revision 1.2 1993/06/03 21:08:08 keving * nothing * * Revision 1.1 1993/02/19 19:14:28 keving * nothing * */ /*==============* * HEADER FILES * *==============*/ #include "all.h" /*#include */ #include #include "mtypes.h" #include "bitio.h" #include "frames.h" #include "prototyp.h" #include "fsize.h" #include "param.h" #include "mheaders.h" #include "postdct.h" /*==================* * STATIC VARIABLES * *==================*/ static int numBIBlocks = 0; static int numBBBlocks = 0; static int numBSkipped = 0; static int numBIBits = 0; static int numBBBits = 0; static int numFrames = 0; static int numFrameBits = 0; static int32 totalTime = 0; static int qscaleB; static float totalSNR = 0.0; static float totalPSNR = 0.0; /*===============================* * INTERNAL PROCEDURE prototypes * *===============================*/ static boolean MotionSufficient _ANSI_ARGS_((LumBlock currBlock, MpegFrame *prev, MpegFrame *next, int by, int bx, int mode, int fmy, int fmx, int bmy, int bmx)); static void ComputeBMotionBlock _ANSI_ARGS_((MpegFrame *prev, MpegFrame *next, int by, int bx, int mode, int fmy, int fmx, int bmy, int bmx, Block motionBlock, int type)); static void ComputeBDiffDCTs _ANSI_ARGS_((MpegFrame *current, MpegFrame *prev, MpegFrame *next, int by, int bx, int mode, int fmy, int fmx, int bmy, int bmx, int pattern)); static boolean DoBIntraCode _ANSI_ARGS_((MpegFrame *current, MpegFrame *prev, MpegFrame *next, int by, int bx, int mode, int fmy, int fmx, int bmy, int bmx)); /*=====================* * EXPORTED PROCEDURES * *=====================*/ /*===========================================================================* * * GenBFrame * * generate a B-frame from previous and next frames, adding the result * to the given bit bucket * * RETURNS: frame appended to bb * * SIDE EFFECTS: none * *===========================================================================*/ void GenBFrame(bb, curr, prev, next) BitBucket *bb; MpegFrame *curr; MpegFrame *prev; MpegFrame *next; { FlatBlock fba[6], fb[6]; Block dec[6]; int32 y_dc_pred, cr_dc_pred, cb_dc_pred; int x, y; int fMotionX = 0, fMotionY = 0; int bMotionX = 0, bMotionY = 0; int oldFMotionX = 0, oldFMotionY = 0; int oldBMotionX = 0, oldBMotionY = 0; int oldMode = MOTION_FORWARD; int mode = MOTION_FORWARD; int offsetX, offsetY; int tempX, tempY; int fMotionXrem = 0, fMotionXquot = 0; int fMotionYrem = 0, fMotionYquot = 0; int bMotionXrem = 0, bMotionXquot = 0; int bMotionYrem = 0, bMotionYquot = 0; int pattern; int numIBlocks = 0; int numBBlocks = 0; int numSkipped = 0; int numIBits = 0; int numBBits = 0; int totalBits; int mbAddrInc = 1; boolean lastIntra = TRUE; int motionForward, motionBackward; int totalFrameBits; /* struct tms timeBuffer; int32 startTime, endTime; */ int lastX, lastY; int lastBlockX, lastBlockY; register int ix, iy; LumBlock currentBlock; int fy, fx; boolean result; int frameBlocks; int slicePos; float snr[3], psnr[3]; int index; numFrames++; totalFrameBits = bb->cumulativeBits; /* times(&timeBuffer); startTime = timeBuffer.tms_utime + timeBuffer.tms_stime; */ Mhead_GenPictureHeader(bb, B_FRAME, curr->id, fCode); Mhead_GenSliceHeader(bb, 1, qscaleB, NULL, 0); Frame_AllocBlocks(curr); BlockifyFrame(curr); if ( printSNR ) { Frame_AllocDecoded(curr, FALSE); } /* for I-blocks */ y_dc_pred = cr_dc_pred = cb_dc_pred = 128; totalBits = bb->cumulativeBits; if ( ! pixelFullSearch ) { if ( ! prev->halfComputed ) { ComputeHalfPixelData(prev); } if ( ! next->halfComputed ) { ComputeHalfPixelData(next); } } lastBlockX = Fsize_x/8; lastBlockY = Fsize_y/8; lastX = lastBlockX-2; lastY = lastBlockY-2; frameBlocks = 0; for (y = 0; y < lastBlockY; y += 2) { for (x = 0; x < lastBlockX; x += 2) { slicePos = (frameBlocks % blocksPerSlice); if ( (slicePos == 0) && (frameBlocks != 0) ) { Mhead_GenSliceEnder(bb); Mhead_GenSliceHeader(bb, 1+(y/2), qscaleB, NULL, 0); /* reset everything */ oldFMotionX = 0; oldFMotionY = 0; oldBMotionX = 0; oldBMotionY = 0; oldMode = MOTION_FORWARD; lastIntra = TRUE; y_dc_pred = cr_dc_pred = cb_dc_pred = 128; mbAddrInc = 1+(x/2); } frameBlocks++; /* compute currentBlock */ BLOCK_TO_FRAME_COORD(y, x, fy, fx); for ( iy = 0; iy < 16; iy++ ) { for ( ix = 0; ix < 16; ix++ ) { currentBlock[iy][ix] = (int16)curr->orig_y[fy+iy][fx+ix]; } } /* STEP 1: Select Forward, Backward, or Interpolated motion vectors */ /* see if old motion is good enough */ /* but force last block to be non-skipped */ /* can only skip if: * 1) not the last block in frame * 2) not the last block in slice * 3) not the first block in slice * 4) previous block was not intra-coded */ if ( ((y < lastY) || (x < lastX)) && (slicePos+1 != blocksPerSlice) && (slicePos != 0) && (! lastIntra) ) { if ( pixelFullSearch ) { result = MotionSufficient(currentBlock, prev, next, y, x, oldMode, 2*oldFMotionY, 2*oldFMotionX, 2*oldBMotionY, 2*oldBMotionX); } else { result = MotionSufficient(currentBlock, prev, next, y, x, oldMode, oldFMotionY, oldFMotionX, oldBMotionY, oldBMotionX); } } else { result = FALSE; } if ( result ) { /* skipped macro block */ mbAddrInc++; numSkipped++; /* decode skipped block */ if ( printSNR ) { int fmy, fmx, bmy, bmx; memset((char *)dec[0], 0, sizeof(Block)); memset((char *)dec[1], 0, sizeof(Block)); memset((char *)dec[2], 0, sizeof(Block)); memset((char *)dec[3], 0, sizeof(Block)); memset((char *)dec[4], 0, sizeof(Block)); memset((char *)dec[5], 0, sizeof(Block)); if ( pixelFullSearch ) { fmy = 2*oldFMotionY; fmx = 2*oldFMotionX; bmy = 2*oldBMotionY; bmx = 2*oldBMotionX; } else { fmy = oldFMotionY; fmx = oldFMotionX; bmy = oldBMotionY; bmx = oldBMotionX; } /* now add the motion block */ AddBMotionBlock(dec[0], prev->decoded_y, next->decoded_y, y, x, mode, fmy, fmx, bmy, bmx); AddBMotionBlock(dec[1], prev->decoded_y, next->decoded_y, y, x+1, mode, fmy, fmx, bmy, bmx); AddBMotionBlock(dec[2], prev->decoded_y, next->decoded_y, y+1, x, mode, fmy, fmx, bmy, bmx); AddBMotionBlock(dec[3], prev->decoded_y, next->decoded_y, y+1, x+1, mode, fmy, fmx, bmy, bmx); AddBMotionBlock(dec[4], prev->decoded_cb, next->decoded_cb, y>>1, x>>1, mode, fmy/2, fmx/2, bmy/2, bmx/2); AddBMotionBlock(dec[5], prev->decoded_cr, next->decoded_cb, y>>1, x>>1, mode, fmy/2, fmx/2, bmy/2, bmx/2); /* now, unblockify */ BlockToData(curr->decoded_y, dec[0], y, x); BlockToData(curr->decoded_y, dec[1], y, x+1); BlockToData(curr->decoded_y, dec[2], y+1, x); BlockToData(curr->decoded_y, dec[3], y+1, x+1); BlockToData(curr->decoded_cb, dec[4], y>>1, x>>1); BlockToData(curr->decoded_cr, dec[5], y>>1, x>>1); } } else { /* do bsearch */ mode = BMotionSearch(currentBlock, prev, next, y, x, &fMotionY, &fMotionX, &bMotionY, &bMotionX, mode); pattern = 63; /* STEP 2: INTRA OR NON-INTRA CODING */ if ( DoBIntraCode(curr, prev, next, y, x, mode, fMotionY, fMotionX, bMotionY, bMotionX) ) { /* output I-block inside a P-frame */ numIBlocks++; /* calculate forward dct's */ mp_fwd_dct_block(curr->y_blocks[y][x]); mp_fwd_dct_block(curr->y_blocks[y][x+1]); mp_fwd_dct_block(curr->y_blocks[y+1][x]); mp_fwd_dct_block(curr->y_blocks[y+1][x+1]); mp_fwd_dct_block(curr->cb_blocks[y >> 1][x >> 1]); mp_fwd_dct_block(curr->cr_blocks[y >> 1][x >> 1]); GEN_I_BLOCK(B_FRAME, curr, bb, mbAddrInc, qscaleB); mbAddrInc = 1; numIBits += (bb->cumulativeBits-totalBits); totalBits = bb->cumulativeBits; /* reset because intra-coded */ oldFMotionX = 0; oldFMotionY = 0; oldBMotionX = 0; oldBMotionY = 0; oldMode = MOTION_FORWARD; lastIntra = TRUE; if ( printSNR ) { /* need to decode block we just encoded */ Mpost_UnQuantZigBlock(fb[0], dec[0], qscaleB, TRUE); Mpost_UnQuantZigBlock(fb[1], dec[1], qscaleB, TRUE); Mpost_UnQuantZigBlock(fb[2], dec[2], qscaleB, TRUE); Mpost_UnQuantZigBlock(fb[3], dec[3], qscaleB, TRUE); Mpost_UnQuantZigBlock(fb[4], dec[4], qscaleB, TRUE); Mpost_UnQuantZigBlock(fb[5], dec[5], qscaleB, TRUE); /* now, reverse the DCT transform */ for ( index = 0; index < 6; index++ ) { j_rev_dct((int16 *)dec[index]); } /* now, unblockify */ BlockToData(curr->decoded_y, dec[0], y, x); BlockToData(curr->decoded_y, dec[1], y, x+1); BlockToData(curr->decoded_y, dec[2], y+1, x); BlockToData(curr->decoded_y, dec[3], y+1, x+1); BlockToData(curr->decoded_cb, dec[4], y>>1, x>>1); BlockToData(curr->decoded_cr, dec[5], y>>1, x>>1); } } else { /* STEP 3: CODED OR NOT CODED */ /* make special cases for (0,0) motion???? */ lastIntra = FALSE; /* USE MOTION VECTORS */ numBBlocks++; /* reset because non-intra-coded */ y_dc_pred = cr_dc_pred = cb_dc_pred = 128; ComputeBDiffDCTs(curr, prev, next, y, x, mode, fMotionY, fMotionX, bMotionY, bMotionX, pattern); if ( pixelFullSearch ) { fMotionX /= 2; fMotionY /= 2; bMotionX /= 2; bMotionY /= 2; } /* should really check to see if same motion as previous block, and see if pattern is 0, then skip it! */ motionForward = ((mode != MOTION_BACKWARD) ? 1 : 0); motionBackward = ((mode != MOTION_FORWARD) ? 1 : 0); if ( motionForward ) { /* transform the fMotion vector into the appropriate values */ offsetX = fMotionX - oldFMotionX; offsetY = fMotionY - oldFMotionY; ENCODE_MOTION_VECTOR(offsetX, offsetY, fMotionXquot, fMotionYquot, fMotionXrem, fMotionYrem, FORW_F); oldFMotionX = fMotionX; oldFMotionY = fMotionY; } if ( motionBackward ) { /* transform the bMotion vector into the appropriate values */ offsetX = bMotionX - oldBMotionX; offsetY = bMotionY - oldBMotionY; ENCODE_MOTION_VECTOR(offsetX, offsetY, bMotionXquot, bMotionYquot, bMotionXrem, bMotionYrem, BACK_F); oldBMotionX = bMotionX; oldBMotionY = bMotionY; } oldMode = mode; if ( pixelFullSearch ) { fMotionX *= 2; fMotionY *= 2; bMotionX *= 2; bMotionY *= 2; } /* create flat blocks and update pattern if necessary */ if ( (pattern & 0x20) && (! Mpost_QuantZigBlock(curr->y_blocks[y][x], fba[0], qscaleB, FALSE)) ) { pattern ^= 0x20; } if ( (pattern & 0x10) && (! Mpost_QuantZigBlock(curr->y_blocks[y][x+1], fba[1], qscaleB, FALSE)) ) { pattern ^= 0x10; } if ( (pattern & 0x8) && (! Mpost_QuantZigBlock(curr->y_blocks[y+1][x], fba[2], qscaleB, FALSE)) ) { pattern ^= 0x8; } if ( (pattern & 0x4) && (! Mpost_QuantZigBlock(curr->y_blocks[y+1][x+1], fba[3], qscaleB, FALSE)) ) { pattern ^= 0x4; } if ( (pattern & 0x2) && (! Mpost_QuantZigBlock(curr->cb_blocks[y >> 1][x >> 1], fba[4], qscaleB, FALSE)) ) { pattern ^= 0x2; } if ( (pattern & 0x1) && (! Mpost_QuantZigBlock(curr->cr_blocks[y >> 1][x >> 1], fba[5], qscaleB, FALSE)) ) { pattern ^= 0x1; } if ( printSNR ) { if ( pattern & 0x20 ) { Mpost_UnQuantZigBlock(fba[0], dec[0], qscaleB, FALSE); } else { memset((char *)dec[0], 0, sizeof(Block)); } if ( pattern & 0x10 ) { Mpost_UnQuantZigBlock(fba[1], dec[1], qscaleB, FALSE); } else { memset((char *)dec[1], 0, sizeof(Block)); } if ( pattern & 0x8 ) { Mpost_UnQuantZigBlock(fba[2], dec[2], qscaleB, FALSE); } else { memset((char *)dec[2], 0, sizeof(Block)); } if ( pattern & 0x4 ) { Mpost_UnQuantZigBlock(fba[3], dec[3], qscaleB, FALSE); } else { memset((char *)dec[3], 0, sizeof(Block)); } if ( pattern & 0x2 ) { Mpost_UnQuantZigBlock(fba[4], dec[4], qscaleB, FALSE); } else { memset((char *)dec[4], 0, sizeof(Block)); } if ( pattern & 0x1 ) { Mpost_UnQuantZigBlock(fba[5], dec[5], qscaleB, FALSE); } else { memset((char *)dec[5], 0, sizeof(Block)); } /* now, reverse the DCT transform */ for ( index = 0; index < 6; index++ ) { if ( GET_ITH_BIT(pattern, 5-index) ) { j_rev_dct((int16 *)dec[index]); } } /* now add the motion block */ AddBMotionBlock(dec[0], prev->decoded_y, next->decoded_y, y, x, mode, fMotionY, fMotionX, bMotionY, bMotionX); AddBMotionBlock(dec[1], prev->decoded_y, next->decoded_y, y, x+1, mode, fMotionY, fMotionX, bMotionY, bMotionX); AddBMotionBlock(dec[2], prev->decoded_y, next->decoded_y, y+1, x, mode, fMotionY, fMotionX, bMotionY, bMotionX); AddBMotionBlock(dec[3], prev->decoded_y, next->decoded_y, y+1, x+1, mode, fMotionY, fMotionX, bMotionY, bMotionX); AddBMotionBlock(dec[4], prev->decoded_cb, next->decoded_cb, y>>1, x>>1, mode, fMotionY/2, fMotionX/2, bMotionY/2, bMotionX/2); AddBMotionBlock(dec[5], prev->decoded_cr, next->decoded_cr, y>>1, x>>1, mode, fMotionY/2, fMotionX/2, bMotionY/2, bMotionX/2); /* now, unblockify */ BlockToData(curr->decoded_y, dec[0], y, x); BlockToData(curr->decoded_y, dec[1], y, x+1); BlockToData(curr->decoded_y, dec[2], y+1, x); BlockToData(curr->decoded_y, dec[3], y+1, x+1); BlockToData(curr->decoded_cb, dec[4], y>>1, x>>1); BlockToData(curr->decoded_cr, dec[5], y>>1, x>>1); } DBG_PRINT(("MB Header(%d,%d)\n", x, y)); Mhead_GenMBHeader(bb, 3 /* pict_code_type */, mbAddrInc /* addr_incr */, 0 /* mb_quant */, 0 /* q_scale */, fCode /* forw_f_code */, fCode /* back_f_code */, fMotionXrem /* horiz_forw_r */, fMotionYrem /* vert_forw_r */, bMotionXrem /* horiz_back_r */, bMotionYrem /* vert_back_r */, motionForward /* motion_forw */, fMotionXquot /* m_horiz_forw */, fMotionYquot /* m_vert_forw */, motionBackward /* motion_back */, bMotionXquot /* m_horiz_back */, bMotionYquot /* m_vert_back */, pattern /* mb_pattern */, 0 /* mb_intra */); mbAddrInc = 1; /* now output the difference */ for ( tempX = 0; tempX < 6; tempX++ ) { if ( GET_ITH_BIT(pattern, 5-tempX) ) { Mpost_RLEHuffPBlock(fba[tempX], bb); } } numBBits += (bb->cumulativeBits-totalBits); totalBits = bb->cumulativeBits; } } } } if ( printSNR ) { ComputeSNR(curr->orig_y, curr->decoded_y, Fsize_y, Fsize_x, &snr[0], &psnr[0]); ComputeSNR(curr->orig_cb, curr->decoded_cb, Fsize_y/2, Fsize_x/2, &snr[1], &psnr[1]); ComputeSNR(curr->orig_cr, curr->decoded_cr, Fsize_y/2, Fsize_x/2, &snr[2], &psnr[2]); totalSNR += snr[0]; totalPSNR += psnr[0]; } Mhead_GenSliceEnder(bb); /* times(&timeBuffer); endTime = timeBuffer.tms_utime + timeBuffer.tms_stime; totalTime += (endTime-startTime); */ /* if ( (! childProcess) && frameSummary ) { fprintf(stdout, "FRAME %d (B): I BLOCKS: %d; B BLOCKS: %d SKIPPED: %d (%ld seconds)\n", curr->id, numIBlocks, numBBlocks, numSkipped, (long)((endTime-startTime)/60)); if ( printSNR ) fprintf(stdout, "FRAME %d: SNR: %.1f\t%.1f\t%.1f\tPSNR: %.1f\t%.1f\t%.1f\n", curr->id, snr[0], snr[1], snr[2], psnr[0], psnr[1], psnr[2]); } */ numFrameBits += (bb->cumulativeBits-totalFrameBits); numBIBlocks += numIBlocks; numBBBlocks += numBBlocks; numBSkipped += numSkipped; numBIBits += numIBits; numBBBits += numBBits; } /*===========================================================================* * * SetBQScale * * set the B-frame Q-scale * * RETURNS: nothing * * SIDE EFFECTS: qscaleB * *===========================================================================*/ void SetBQScale(qB) int qB; { qscaleB = qB; } /*===========================================================================* * * GetBQScale * * get the B-frame Q-scale * * RETURNS: the Q-scale * * SIDE EFFECTS: none * *===========================================================================*/ int GetBQScale() { return qscaleB; } /*===========================================================================* * * ResetBFrameStats * * reset the B-frame stats * * RETURNS: nothing * * SIDE EFFECTS: none * *===========================================================================*/ void ResetBFrameStats() { numBIBlocks = 0; numBBBlocks = 0; numBSkipped = 0; numBIBits = 0; numBBBits = 0; numFrames = 0; numFrameBits = 0; totalTime = 0; } /*===========================================================================* * * ShowBFrameSummary * * print out statistics on all B-frames * * RETURNS: nothing * * SIDE EFFECTS: none * *===========================================================================*/ /* void ShowBFrameSummary(inputFrameBits, totalBits, fpointer) int inputFrameBits; int32 totalBits; FILE *fpointer; { if ( numFrames == 0 ) { return; } fprintf(fpointer, "-------------------------\n"); fprintf(fpointer, "*****B FRAME SUMMARY*****\n"); fprintf(fpointer, "-------------------------\n"); if ( numBIBlocks != 0 ) { fprintf(fpointer, " I Blocks: %5d (%6d bits) (%5d bpb)\n", numBIBlocks, numBIBits, numBIBits/numBIBlocks); } else { fprintf(fpointer, " I Blocks: %5d\n", 0); } if ( numBBBlocks != 0 ) { fprintf(fpointer, " B Blocks: %5d (%6d bits) (%5d bpb)\n", numBBBlocks, numBBBits, numBBBits/numBBBlocks); } else { fprintf(fpointer, " B Blocks: %5d\n", 0); } fprintf(fpointer, " Skipped: %5d\n", numBSkipped); fprintf(fpointer, " Frames: %5d (%6d bits) (%5d bpf) (%2.1f%% of total)\n", numFrames, numFrameBits, numFrameBits/numFrames, 100.0*(float)numFrameBits/(float)totalBits); fprintf(fpointer, " Compression: %3d:1\n", numFrames*inputFrameBits/numFrameBits); if ( printSNR ) fprintf(fpointer, " Avg Y SNR/PSNR: %.1f %.1f\n", totalSNR/(float)numFrames, totalPSNR/(float)numFrames); fprintf(fpointer, " Seconds: %9ld (%9ld spf) (%9ld bps)\n", (long)(totalTime/60), (long)(totalTime/(60*numFrames)), (long)(60.0*(float)numFrames*(float)inputFrameBits/(float)totalTime)); } */ /*===========================================================================* * * ComputeBMotionLumBlock * * compute the luminance block resulting from motion compensation * * RETURNS: motionBlock modified * * SIDE EFFECTS: none * * PRECONDITION: the motion vectors must be valid! * *===========================================================================*/ void ComputeBMotionLumBlock(prev, next, by, bx, mode, fmy, fmx, bmy, bmx, motionBlock) MpegFrame *prev; MpegFrame *next; int by; int bx; int mode; int fmy; int fmx; int bmy; int bmx; LumBlock motionBlock; { LumBlock prevBlock, nextBlock; register int y, x; switch(mode) { case MOTION_FORWARD: ComputeMotionLumBlock(prev, by, bx, fmy, fmx, motionBlock); break; case MOTION_BACKWARD: ComputeMotionLumBlock(next, by, bx, bmy, bmx, motionBlock); break; case MOTION_INTERPOLATE: ComputeMotionLumBlock(prev, by, bx, fmy, fmx, prevBlock); ComputeMotionLumBlock(next, by, bx, bmy, bmx, nextBlock); for ( y = 0; y < 16; y++ ) { for ( x = 0; x < 16; x++ ) { motionBlock[y][x] = (prevBlock[y][x]+nextBlock[y][x]+1)/2; } } break; } } /*===========================================================================* * * EstimateSecondsPerBFrame * * estimate the seconds to compute a B-frame * * RETURNS: the time, in seconds * * SIDE EFFECTS: none * *===========================================================================*/ /* float EstimateSecondsPerBFrame() { if ( numFrames == 0 ) { return 20.0; } else { return (float)totalTime/(60.0*(float)numFrames); } } */ /*=====================* * INTERNAL PROCEDURES * *=====================*/ /*===========================================================================* * * ComputeBMotionBlock * * compute the block resulting from motion compensation * * RETURNS: motionBlock is modified * * SIDE EFFECTS: none * * PRECONDITION: the motion vectors must be valid! * *===========================================================================*/ static void ComputeBMotionBlock(prev, next, by, bx, mode, fmy, fmx, bmy, bmx, motionBlock, type) MpegFrame *prev; MpegFrame *next; int by; int bx; int mode; int fmy; int fmx; int bmy; int bmx; Block motionBlock; int type; { Block prevBlock, nextBlock; register int y, x; switch(mode) { case MOTION_FORWARD: if ( type == LUM_BLOCK ) { ComputeMotionBlock(prev->ref_y, by, bx, fmy, fmx, motionBlock); } else if ( type == CB_BLOCK ) { ComputeMotionBlock(prev->ref_cb, by, bx, fmy, fmx, motionBlock); } else if ( type == CR_BLOCK ) { ComputeMotionBlock(prev->ref_cr, by, bx, fmy, fmx, motionBlock); } break; case MOTION_BACKWARD: if ( type == LUM_BLOCK ) { ComputeMotionBlock(next->ref_y, by, bx, bmy, bmx, motionBlock); } else if ( type == CB_BLOCK ) { ComputeMotionBlock(next->ref_cb, by, bx, bmy, bmx, motionBlock); } else if ( type == CR_BLOCK ) { ComputeMotionBlock(next->ref_cr, by, bx, bmy, bmx, motionBlock); } break; case MOTION_INTERPOLATE: if ( type == LUM_BLOCK ) { ComputeMotionBlock(prev->ref_y, by, bx, fmy, fmx, prevBlock); ComputeMotionBlock(next->ref_y, by, bx, bmy, bmx, nextBlock); } else if ( type == CB_BLOCK ) { ComputeMotionBlock(prev->ref_cb, by, bx, fmy, fmx, prevBlock); ComputeMotionBlock(next->ref_cb, by, bx, bmy, bmx, nextBlock); } else if ( type == CR_BLOCK ) { ComputeMotionBlock(prev->ref_cr, by, bx, fmy, fmx, prevBlock); ComputeMotionBlock(next->ref_cr, by, bx, bmy, bmx, nextBlock); } for ( y = 0; y < 8; y++ ) { for ( x = 0; x < 8; x++ ) { motionBlock[y][x] = (prevBlock[y][x]+nextBlock[y][x]+1)/2; } } break; } } /*===========================================================================* * * ComputeBDiffDCTs * * compute the DCT of the error term * * RETURNS: appropriate blocks of current will contain the DCTs * * SIDE EFFECTS: none * * PRECONDITION: the motion vectors must be valid! * *===========================================================================*/ static void ComputeBDiffDCTs(current, prev, next, by, bx, mode, fmy, fmx, bmy, bmx, pattern) MpegFrame *current; MpegFrame *prev; MpegFrame *next; int by; int bx; int mode; int fmy; int fmx; int bmy; int bmx; int pattern; { Block motionBlock; if ( pattern & 0x20 ) { ComputeBMotionBlock(prev, next, by, bx, mode, fmy, fmx, bmy, bmx, motionBlock, LUM_BLOCK); ComputeDiffDCTBlock(current->y_blocks[by][bx], motionBlock); } if ( pattern & 0x10 ) { ComputeBMotionBlock(prev, next, by, bx+1, mode, fmy, fmx, bmy, bmx, motionBlock, LUM_BLOCK); ComputeDiffDCTBlock(current->y_blocks[by][bx+1], motionBlock); } if ( pattern & 0x8 ) { ComputeBMotionBlock(prev, next, by+1, bx, mode, fmy, fmx, bmy, bmx, motionBlock, LUM_BLOCK); ComputeDiffDCTBlock(current->y_blocks[by+1][bx], motionBlock); } if ( pattern & 0x4 ) { ComputeBMotionBlock(prev, next, by+1, bx+1, mode, fmy, fmx, bmy, bmx, motionBlock, LUM_BLOCK); ComputeDiffDCTBlock(current->y_blocks[by+1][bx+1], motionBlock); } if ( pattern & 0x2 ) { ComputeBMotionBlock(prev, next, by>>1, bx>>1, mode, fmy/2, fmx/2, bmy/2, bmx/2, motionBlock, CB_BLOCK); ComputeDiffDCTBlock(current->cb_blocks[by >> 1][bx >> 1], motionBlock); } if ( pattern & 0x1 ) { ComputeBMotionBlock(prev, next, by>>1, bx>>1, mode, fmy/2, fmx/2, bmy/2, bmx/2, motionBlock, CR_BLOCK); ComputeDiffDCTBlock(current->cr_blocks[by >> 1][bx >> 1], motionBlock); } } /*===========================================================================* * * USER-MODIFIABLE * * DoBIntraCode * * decides if this block should be coded as intra-block * * RETURNS: TRUE if intra-coding should be used; FALSE otherwise * * SIDE EFFECTS: none * * PRECONDITION: the motion vectors must be valid! * *===========================================================================*/ static boolean DoBIntraCode(current, prev, next, by, bx, mode, fmy, fmx, bmy, bmx) MpegFrame *current; MpegFrame *prev; MpegFrame *next; int by; int bx; int mode; int fmy; int fmx; int bmy; int bmx; { int x, y; int32 sum = 0, vard = 0, varc = 0, dif; int32 currPixel, prevPixel; LumBlock motionBlock; int fy, fx; ComputeBMotionLumBlock(prev, next, by, bx, mode, fmy, fmx, bmy, bmx, motionBlock); MOTION_TO_FRAME_COORD(by, bx, 0, 0, fy, fx); for ( y = 0; y < 16; y++ ) { for ( x = 0; x < 16; x++ ) { currPixel = current->orig_y[fy+y][fx+x]; prevPixel = motionBlock[y][x]; sum += currPixel; varc += currPixel*currPixel; dif = currPixel - prevPixel; vard += dif*dif; } } vard /= 256; /* assumes mean is close to zero */ varc = varc/256 - (sum/256)*(sum/256); if ( vard <= 64 ) { return FALSE; } else if ( vard < varc ) { return FALSE; } else { return TRUE; } } /*===========================================================================* * * USER-MODIFIABLE * * MotionSufficient * * decides if this motion vector is sufficient without DCT coding * * RETURNS: TRUE if no DCT is needed; FALSE otherwise * * SIDE EFFECTS: none * * PRECONDITION: the motion vectors must be valid! * *===========================================================================*/ static boolean MotionSufficient(currBlock, prev, next, by, bx, mode, fmy, fmx, bmy, bmx) LumBlock currBlock; MpegFrame *prev; MpegFrame *next; int by; int bx; int mode; int fmy; int fmx; int bmy; int bmx; { LumBlock motionBlock; if ( mode != MOTION_BACKWARD ) { /* check forward motion for bounds */ if ( (by*DCTSIZE+(fmy-1)/2 < 0) || ((by+2)*DCTSIZE+(fmy+1)/2-1 >= Fsize_y) ) { return FALSE; } if ( (bx*DCTSIZE+(fmx-1)/2 < 0) || ((bx+2)*DCTSIZE+(fmx+1)/2-1 >= Fsize_x) ) { return FALSE; } } if ( mode != MOTION_FORWARD ) { /* check backward motion for bounds */ if ( (by*DCTSIZE+(bmy-1)/2 < 0) || ((by+2)*DCTSIZE+(bmy+1)/2-1 >= Fsize_y) ) { return FALSE; } if ( (bx*DCTSIZE+(bmx-1)/2 < 0) || ((bx+2)*DCTSIZE+(bmx+1)/2-1 >= Fsize_x) ) { return FALSE; } } ComputeBMotionLumBlock(prev, next, by, bx, mode, fmy, fmx, bmy, bmx, motionBlock); return (LumBlockMAD(currBlock, motionBlock, 0x7fffffff) <= 512); }