+ // transform
+ transformDataUnit(quantTable, dataIn, dataOut);
+
+ // store back into frameBuf, doing replication for
+ // subsampled components
+ p1 = &frameBuf[cc][(y1+y2) * bufWidth + (x1+x2)];
+ if (hSub == 1 && vSub == 1) {
+ for (y3 = 0, i = 0; y3 < 8; ++y3, i += 8) {
+ p1[0] = dataOut[i] & 0xff;
+ p1[1] = dataOut[i+1] & 0xff;
+ p1[2] = dataOut[i+2] & 0xff;
+ p1[3] = dataOut[i+3] & 0xff;
+ p1[4] = dataOut[i+4] & 0xff;
+ p1[5] = dataOut[i+5] & 0xff;
+ p1[6] = dataOut[i+6] & 0xff;
+ p1[7] = dataOut[i+7] & 0xff;
+ p1 += bufWidth;
+ }
+ } else if (hSub == 2 && vSub == 2) {
+ p2 = p1 + bufWidth;
+ for (y3 = 0, i = 0; y3 < 16; y3 += 2, i += 8) {
+ p1[0] = p1[1] = p2[0] = p2[1] = dataOut[i] & 0xff;
+ p1[2] = p1[3] = p2[2] = p2[3] = dataOut[i+1] & 0xff;
+ p1[4] = p1[5] = p2[4] = p2[5] = dataOut[i+2] & 0xff;
+ p1[6] = p1[7] = p2[6] = p2[7] = dataOut[i+3] & 0xff;
+ p1[8] = p1[9] = p2[8] = p2[9] = dataOut[i+4] & 0xff;
+ p1[10] = p1[11] = p2[10] = p2[11] = dataOut[i+5] & 0xff;
+ p1[12] = p1[13] = p2[12] = p2[13] = dataOut[i+6] & 0xff;
+ p1[14] = p1[15] = p2[14] = p2[15] = dataOut[i+7] & 0xff;
+ p1 += bufWidth * 2;
+ p2 += bufWidth * 2;
+ }
+ } else {
+ i = 0;
+ for (y3 = 0, y4 = 0; y3 < 8; ++y3, y4 += vSub) {
+ for (x3 = 0, x4 = 0; x3 < 8; ++x3, x4 += hSub) {
+ p2 = p1 + x4;
+ for (y5 = 0; y5 < vSub; ++y5) {
+ for (x5 = 0; x5 < hSub; ++x5) {
+ p2[x5] = dataOut[i] & 0xff;
+ }
+ p2 += bufWidth;
+ }
+ ++i;
+ }
+ p1 += bufWidth * vSub;
+ }
+ }
+ }
+ }
+ }
+
+ // color space conversion
+ if (colorXform) {
+ // convert YCbCr to RGB
+ if (numComps == 3) {
+ for (y2 = 0; y2 < mcuHeight; ++y2) {
+ p0 = &frameBuf[0][(y1+y2) * bufWidth + x1];
+ p1 = &frameBuf[1][(y1+y2) * bufWidth + x1];
+ p2 = &frameBuf[2][(y1+y2) * bufWidth + x1];
+ for (x2 = 0; x2 < mcuWidth; ++x2) {
+ pY = *p0;
+ pCb = *p1 - 128;
+ pCr = *p2 - 128;
+ pR = ((pY << 16) + dctCrToR * pCr + 32768) >> 16;
+ *p0++ = dctClip[dctClipOffset + pR];
+ pG = ((pY << 16) + dctCbToG * pCb + dctCrToG * pCr +
+ 32768) >> 16;
+ *p1++ = dctClip[dctClipOffset + pG];
+ pB = ((pY << 16) + dctCbToB * pCb + 32768) >> 16;
+ *p2++ = dctClip[dctClipOffset + pB];
+ }
+ }
+ // convert YCbCrK to CMYK (K is passed through unchanged)
+ } else if (numComps == 4) {
+ for (y2 = 0; y2 < mcuHeight; ++y2) {
+ p0 = &frameBuf[0][(y1+y2) * bufWidth + x1];
+ p1 = &frameBuf[1][(y1+y2) * bufWidth + x1];
+ p2 = &frameBuf[2][(y1+y2) * bufWidth + x1];
+ for (x2 = 0; x2 < mcuWidth; ++x2) {
+ pY = *p0;
+ pCb = *p1 - 128;
+ pCr = *p2 - 128;
+ pR = ((pY << 16) + dctCrToR * pCr + 32768) >> 16;
+ *p0++ = 255 - dctClip[dctClipOffset + pR];
+ pG = ((pY << 16) + dctCbToG * pCb + dctCrToG * pCr +
+ 32768) >> 16;
+ *p1++ = 255 - dctClip[dctClipOffset + pG];
+ pB = ((pY << 16) + dctCbToB * pCb + 32768) >> 16;
+ *p2++ = 255 - dctClip[dctClipOffset + pB];
+ }
+ }
+ }
+ }