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swscale.c
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1 /*
2  * Copyright (C) 2001-2011 Michael Niedermayer <michaelni@gmx.at>
3  *
4  * This file is part of FFmpeg.
5  *
6  * FFmpeg is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU Lesser General Public
8  * License as published by the Free Software Foundation; either
9  * version 2.1 of the License, or (at your option) any later version.
10  *
11  * FFmpeg is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14  * Lesser General Public License for more details.
15  *
16  * You should have received a copy of the GNU Lesser General Public
17  * License along with FFmpeg; if not, write to the Free Software
18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19  */
20 
21 #include <inttypes.h>
22 #include <math.h>
23 #include <stdio.h>
24 #include <string.h>
25 
26 #include "libavutil/avassert.h"
27 #include "libavutil/avutil.h"
28 #include "libavutil/bswap.h"
29 #include "libavutil/cpu.h"
30 #include "libavutil/intreadwrite.h"
31 #include "libavutil/mathematics.h"
32 #include "libavutil/pixdesc.h"
33 #include "config.h"
34 #include "rgb2rgb.h"
35 #include "swscale_internal.h"
36 #include "swscale.h"
37 
39  { 36, 68, 60, 92, 34, 66, 58, 90, },
40  { 100, 4, 124, 28, 98, 2, 122, 26, },
41  { 52, 84, 44, 76, 50, 82, 42, 74, },
42  { 116, 20, 108, 12, 114, 18, 106, 10, },
43  { 32, 64, 56, 88, 38, 70, 62, 94, },
44  { 96, 0, 120, 24, 102, 6, 126, 30, },
45  { 48, 80, 40, 72, 54, 86, 46, 78, },
46  { 112, 16, 104, 8, 118, 22, 110, 14, },
47  { 36, 68, 60, 92, 34, 66, 58, 90, },
48 };
49 
50 DECLARE_ALIGNED(8, static const uint8_t, sws_pb_64)[8] = {
51  64, 64, 64, 64, 64, 64, 64, 64
52 };
53 
54 static av_always_inline void fillPlane(uint8_t *plane, int stride, int width,
55  int height, int y, uint8_t val)
56 {
57  int i;
58  uint8_t *ptr = plane + stride * y;
59  for (i = 0; i < height; i++) {
60  memset(ptr, val, width);
61  ptr += stride;
62  }
63 }
64 
65 static void hScale16To19_c(SwsContext *c, int16_t *_dst, int dstW,
66  const uint8_t *_src, const int16_t *filter,
67  const int32_t *filterPos, int filterSize)
68 {
70  int i;
71  int32_t *dst = (int32_t *) _dst;
72  const uint16_t *src = (const uint16_t *) _src;
73  int bits = desc->comp[0].depth_minus1;
74  int sh = bits - 4;
75 
76  if((isAnyRGB(c->srcFormat) || c->srcFormat==AV_PIX_FMT_PAL8) && desc->comp[0].depth_minus1<15)
77  sh= 9;
78 
79  for (i = 0; i < dstW; i++) {
80  int j;
81  int srcPos = filterPos[i];
82  int val = 0;
83 
84  for (j = 0; j < filterSize; j++) {
85  val += src[srcPos + j] * filter[filterSize * i + j];
86  }
87  // filter=14 bit, input=16 bit, output=30 bit, >> 11 makes 19 bit
88  dst[i] = FFMIN(val >> sh, (1 << 19) - 1);
89  }
90 }
91 
92 static void hScale16To15_c(SwsContext *c, int16_t *dst, int dstW,
93  const uint8_t *_src, const int16_t *filter,
94  const int32_t *filterPos, int filterSize)
95 {
97  int i;
98  const uint16_t *src = (const uint16_t *) _src;
99  int sh = desc->comp[0].depth_minus1;
100 
101  if(sh<15)
102  sh= isAnyRGB(c->srcFormat) || c->srcFormat==AV_PIX_FMT_PAL8 ? 13 : desc->comp[0].depth_minus1;
103 
104  for (i = 0; i < dstW; i++) {
105  int j;
106  int srcPos = filterPos[i];
107  int val = 0;
108 
109  for (j = 0; j < filterSize; j++) {
110  val += src[srcPos + j] * filter[filterSize * i + j];
111  }
112  // filter=14 bit, input=16 bit, output=30 bit, >> 15 makes 15 bit
113  dst[i] = FFMIN(val >> sh, (1 << 15) - 1);
114  }
115 }
116 
117 // bilinear / bicubic scaling
118 static void hScale8To15_c(SwsContext *c, int16_t *dst, int dstW,
119  const uint8_t *src, const int16_t *filter,
120  const int32_t *filterPos, int filterSize)
121 {
122  int i;
123  for (i = 0; i < dstW; i++) {
124  int j;
125  int srcPos = filterPos[i];
126  int val = 0;
127  for (j = 0; j < filterSize; j++) {
128  val += ((int)src[srcPos + j]) * filter[filterSize * i + j];
129  }
130  dst[i] = FFMIN(val >> 7, (1 << 15) - 1); // the cubic equation does overflow ...
131  }
132 }
133 
134 static void hScale8To19_c(SwsContext *c, int16_t *_dst, int dstW,
135  const uint8_t *src, const int16_t *filter,
136  const int32_t *filterPos, int filterSize)
137 {
138  int i;
139  int32_t *dst = (int32_t *) _dst;
140  for (i = 0; i < dstW; i++) {
141  int j;
142  int srcPos = filterPos[i];
143  int val = 0;
144  for (j = 0; j < filterSize; j++) {
145  val += ((int)src[srcPos + j]) * filter[filterSize * i + j];
146  }
147  dst[i] = FFMIN(val >> 3, (1 << 19) - 1); // the cubic equation does overflow ...
148  }
149 }
150 
151 // FIXME all pal and rgb srcFormats could do this conversion as well
152 // FIXME all scalers more complex than bilinear could do half of this transform
153 static void chrRangeToJpeg_c(int16_t *dstU, int16_t *dstV, int width)
154 {
155  int i;
156  for (i = 0; i < width; i++) {
157  dstU[i] = (FFMIN(dstU[i], 30775) * 4663 - 9289992) >> 12; // -264
158  dstV[i] = (FFMIN(dstV[i], 30775) * 4663 - 9289992) >> 12; // -264
159  }
160 }
161 
162 static void chrRangeFromJpeg_c(int16_t *dstU, int16_t *dstV, int width)
163 {
164  int i;
165  for (i = 0; i < width; i++) {
166  dstU[i] = (dstU[i] * 1799 + 4081085) >> 11; // 1469
167  dstV[i] = (dstV[i] * 1799 + 4081085) >> 11; // 1469
168  }
169 }
170 
171 static void lumRangeToJpeg_c(int16_t *dst, int width)
172 {
173  int i;
174  for (i = 0; i < width; i++)
175  dst[i] = (FFMIN(dst[i], 30189) * 19077 - 39057361) >> 14;
176 }
177 
178 static void lumRangeFromJpeg_c(int16_t *dst, int width)
179 {
180  int i;
181  for (i = 0; i < width; i++)
182  dst[i] = (dst[i] * 14071 + 33561947) >> 14;
183 }
184 
185 static void chrRangeToJpeg16_c(int16_t *_dstU, int16_t *_dstV, int width)
186 {
187  int i;
188  int32_t *dstU = (int32_t *) _dstU;
189  int32_t *dstV = (int32_t *) _dstV;
190  for (i = 0; i < width; i++) {
191  dstU[i] = (FFMIN(dstU[i], 30775 << 4) * 4663 - (9289992 << 4)) >> 12; // -264
192  dstV[i] = (FFMIN(dstV[i], 30775 << 4) * 4663 - (9289992 << 4)) >> 12; // -264
193  }
194 }
195 
196 static void chrRangeFromJpeg16_c(int16_t *_dstU, int16_t *_dstV, int width)
197 {
198  int i;
199  int32_t *dstU = (int32_t *) _dstU;
200  int32_t *dstV = (int32_t *) _dstV;
201  for (i = 0; i < width; i++) {
202  dstU[i] = (dstU[i] * 1799 + (4081085 << 4)) >> 11; // 1469
203  dstV[i] = (dstV[i] * 1799 + (4081085 << 4)) >> 11; // 1469
204  }
205 }
206 
207 static void lumRangeToJpeg16_c(int16_t *_dst, int width)
208 {
209  int i;
210  int32_t *dst = (int32_t *) _dst;
211  for (i = 0; i < width; i++)
212  dst[i] = (FFMIN(dst[i], 30189 << 4) * 4769 - (39057361 << 2)) >> 12;
213 }
214 
215 static void lumRangeFromJpeg16_c(int16_t *_dst, int width)
216 {
217  int i;
218  int32_t *dst = (int32_t *) _dst;
219  for (i = 0; i < width; i++)
220  dst[i] = (dst[i]*(14071/4) + (33561947<<4)/4)>>12;
221 }
222 
223 static void hyscale_fast_c(SwsContext *c, int16_t *dst, int dstWidth,
224  const uint8_t *src, int srcW, int xInc)
225 {
226  int i;
227  unsigned int xpos = 0;
228  for (i = 0; i < dstWidth; i++) {
229  register unsigned int xx = xpos >> 16;
230  register unsigned int xalpha = (xpos & 0xFFFF) >> 9;
231  dst[i] = (src[xx] << 7) + (src[xx + 1] - src[xx]) * xalpha;
232  xpos += xInc;
233  }
234  for (i=dstWidth-1; (i*xInc)>>16 >=srcW-1; i--)
235  dst[i] = src[srcW-1]*128;
236 }
237 
238 // *** horizontal scale Y line to temp buffer
239 static av_always_inline void hyscale(SwsContext *c, int16_t *dst, int dstWidth,
240  const uint8_t *src_in[4],
241  int srcW, int xInc,
242  const int16_t *hLumFilter,
243  const int32_t *hLumFilterPos,
244  int hLumFilterSize,
246  uint32_t *pal, int isAlpha)
247 {
248  void (*toYV12)(uint8_t *, const uint8_t *, const uint8_t *, const uint8_t *, int, uint32_t *) =
249  isAlpha ? c->alpToYV12 : c->lumToYV12;
250  void (*convertRange)(int16_t *, int) = isAlpha ? NULL : c->lumConvertRange;
251  const uint8_t *src = src_in[isAlpha ? 3 : 0];
252 
253  if (toYV12) {
254  toYV12(formatConvBuffer, src, src_in[1], src_in[2], srcW, pal);
256  } else if (c->readLumPlanar && !isAlpha) {
257  c->readLumPlanar(formatConvBuffer, src_in, srcW, c->input_rgb2yuv_table);
259  } else if (c->readAlpPlanar && isAlpha) {
260  c->readAlpPlanar(formatConvBuffer, src_in, srcW, NULL);
262  }
263 
264  if (!c->hyscale_fast) {
265  c->hyScale(c, dst, dstWidth, src, hLumFilter,
266  hLumFilterPos, hLumFilterSize);
267  } else { // fast bilinear upscale / crap downscale
268  c->hyscale_fast(c, dst, dstWidth, src, srcW, xInc);
269  }
270 
271  if (convertRange)
272  convertRange(dst, dstWidth);
273 }
274 
275 static void hcscale_fast_c(SwsContext *c, int16_t *dst1, int16_t *dst2,
276  int dstWidth, const uint8_t *src1,
277  const uint8_t *src2, int srcW, int xInc)
278 {
279  int i;
280  unsigned int xpos = 0;
281  for (i = 0; i < dstWidth; i++) {
282  register unsigned int xx = xpos >> 16;
283  register unsigned int xalpha = (xpos & 0xFFFF) >> 9;
284  dst1[i] = (src1[xx] * (xalpha ^ 127) + src1[xx + 1] * xalpha);
285  dst2[i] = (src2[xx] * (xalpha ^ 127) + src2[xx + 1] * xalpha);
286  xpos += xInc;
287  }
288  for (i=dstWidth-1; (i*xInc)>>16 >=srcW-1; i--) {
289  dst1[i] = src1[srcW-1]*128;
290  dst2[i] = src2[srcW-1]*128;
291  }
292 }
293 
294 static av_always_inline void hcscale(SwsContext *c, int16_t *dst1,
295  int16_t *dst2, int dstWidth,
296  const uint8_t *src_in[4],
297  int srcW, int xInc,
298  const int16_t *hChrFilter,
299  const int32_t *hChrFilterPos,
300  int hChrFilterSize,
301  uint8_t *formatConvBuffer, uint32_t *pal)
302 {
303  const uint8_t *src1 = src_in[1], *src2 = src_in[2];
304  if (c->chrToYV12) {
305  uint8_t *buf2 = formatConvBuffer +
306  FFALIGN(srcW*2+78, 16);
307  c->chrToYV12(formatConvBuffer, buf2, src_in[0], src1, src2, srcW, pal);
308  src1= formatConvBuffer;
309  src2= buf2;
310  } else if (c->readChrPlanar) {
311  uint8_t *buf2 = formatConvBuffer +
312  FFALIGN(srcW*2+78, 16);
313  c->readChrPlanar(formatConvBuffer, buf2, src_in, srcW, c->input_rgb2yuv_table);
314  src1 = formatConvBuffer;
315  src2 = buf2;
316  }
317 
318  if (!c->hcscale_fast) {
319  c->hcScale(c, dst1, dstWidth, src1, hChrFilter, hChrFilterPos, hChrFilterSize);
320  c->hcScale(c, dst2, dstWidth, src2, hChrFilter, hChrFilterPos, hChrFilterSize);
321  } else { // fast bilinear upscale / crap downscale
322  c->hcscale_fast(c, dst1, dst2, dstWidth, src1, src2, srcW, xInc);
323  }
324 
325  if (c->chrConvertRange)
326  c->chrConvertRange(dst1, dst2, dstWidth);
327 }
328 
329 #define DEBUG_SWSCALE_BUFFERS 0
330 #define DEBUG_BUFFERS(...) \
331  if (DEBUG_SWSCALE_BUFFERS) \
332  av_log(c, AV_LOG_DEBUG, __VA_ARGS__)
333 
334 static int swscale(SwsContext *c, const uint8_t *src[],
335  int srcStride[], int srcSliceY,
336  int srcSliceH, uint8_t *dst[], int dstStride[])
337 {
338  /* load a few things into local vars to make the code more readable?
339  * and faster */
340  const int srcW = c->srcW;
341  const int dstW = c->dstW;
342  const int dstH = c->dstH;
343  const int chrDstW = c->chrDstW;
344  const int chrSrcW = c->chrSrcW;
345  const int lumXInc = c->lumXInc;
346  const int chrXInc = c->chrXInc;
347  const enum AVPixelFormat dstFormat = c->dstFormat;
348  const int flags = c->flags;
353  int16_t *hLumFilter = c->hLumFilter;
354  int16_t *hChrFilter = c->hChrFilter;
357  const int vLumFilterSize = c->vLumFilterSize;
358  const int vChrFilterSize = c->vChrFilterSize;
359  const int hLumFilterSize = c->hLumFilterSize;
360  const int hChrFilterSize = c->hChrFilterSize;
361  int16_t **lumPixBuf = c->lumPixBuf;
362  int16_t **chrUPixBuf = c->chrUPixBuf;
363  int16_t **chrVPixBuf = c->chrVPixBuf;
364  int16_t **alpPixBuf = c->alpPixBuf;
365  const int vLumBufSize = c->vLumBufSize;
366  const int vChrBufSize = c->vChrBufSize;
368  uint32_t *pal = c->pal_yuv;
376  const int chrSrcSliceY = srcSliceY >> c->chrSrcVSubSample;
377  const int chrSrcSliceH = FF_CEIL_RSHIFT(srcSliceH, c->chrSrcVSubSample);
378  int should_dither = is9_OR_10BPS(c->srcFormat) ||
379  is16BPS(c->srcFormat);
380  int lastDstY;
381 
382  /* vars which will change and which we need to store back in the context */
383  int dstY = c->dstY;
384  int lumBufIndex = c->lumBufIndex;
385  int chrBufIndex = c->chrBufIndex;
386  int lastInLumBuf = c->lastInLumBuf;
387  int lastInChrBuf = c->lastInChrBuf;
388 
389  if (!usePal(c->srcFormat)) {
390  pal = c->input_rgb2yuv_table;
391  }
392 
393  if (isPacked(c->srcFormat)) {
394  src[0] =
395  src[1] =
396  src[2] =
397  src[3] = src[0];
398  srcStride[0] =
399  srcStride[1] =
400  srcStride[2] =
401  srcStride[3] = srcStride[0];
402  }
403  srcStride[1] <<= c->vChrDrop;
404  srcStride[2] <<= c->vChrDrop;
405 
406  DEBUG_BUFFERS("swscale() %p[%d] %p[%d] %p[%d] %p[%d] -> %p[%d] %p[%d] %p[%d] %p[%d]\n",
407  src[0], srcStride[0], src[1], srcStride[1],
408  src[2], srcStride[2], src[3], srcStride[3],
409  dst[0], dstStride[0], dst[1], dstStride[1],
410  dst[2], dstStride[2], dst[3], dstStride[3]);
411  DEBUG_BUFFERS("srcSliceY: %d srcSliceH: %d dstY: %d dstH: %d\n",
412  srcSliceY, srcSliceH, dstY, dstH);
413  DEBUG_BUFFERS("vLumFilterSize: %d vLumBufSize: %d vChrFilterSize: %d vChrBufSize: %d\n",
414  vLumFilterSize, vLumBufSize, vChrFilterSize, vChrBufSize);
415 
416  if (dstStride[0]%16 !=0 || dstStride[1]%16 !=0 ||
417  dstStride[2]%16 !=0 || dstStride[3]%16 != 0) {
418  static int warnedAlready = 0; // FIXME maybe move this into the context
419  if (flags & SWS_PRINT_INFO && !warnedAlready) {
421  "Warning: dstStride is not aligned!\n"
422  " ->cannot do aligned memory accesses anymore\n");
423  warnedAlready = 1;
424  }
425  }
426 
427  if ( (uintptr_t)dst[0]%16 || (uintptr_t)dst[1]%16 || (uintptr_t)dst[2]%16
428  || (uintptr_t)src[0]%16 || (uintptr_t)src[1]%16 || (uintptr_t)src[2]%16
429  || dstStride[0]%16 || dstStride[1]%16 || dstStride[2]%16 || dstStride[3]%16
430  || srcStride[0]%16 || srcStride[1]%16 || srcStride[2]%16 || srcStride[3]%16
431  ) {
432  static int warnedAlready=0;
433  int cpu_flags = av_get_cpu_flags();
434  if (HAVE_MMXEXT && (cpu_flags & AV_CPU_FLAG_SSE2) && !warnedAlready){
435  av_log(c, AV_LOG_WARNING, "Warning: data is not aligned! This can lead to a speedloss\n");
436  warnedAlready=1;
437  }
438  }
439 
440  /* Note the user might start scaling the picture in the middle so this
441  * will not get executed. This is not really intended but works
442  * currently, so people might do it. */
443  if (srcSliceY == 0) {
444  lumBufIndex = -1;
445  chrBufIndex = -1;
446  dstY = 0;
447  lastInLumBuf = -1;
448  lastInChrBuf = -1;
449  }
450 
451  if (!should_dither) {
452  c->chrDither8 = c->lumDither8 = sws_pb_64;
453  }
454  lastDstY = dstY;
455 
456  for (; dstY < dstH; dstY++) {
457  const int chrDstY = dstY >> c->chrDstVSubSample;
458  uint8_t *dest[4] = {
459  dst[0] + dstStride[0] * dstY,
460  dst[1] + dstStride[1] * chrDstY,
461  dst[2] + dstStride[2] * chrDstY,
462  (CONFIG_SWSCALE_ALPHA && alpPixBuf) ? dst[3] + dstStride[3] * dstY : NULL,
463  };
465 
466  // First line needed as input
467  const int firstLumSrcY = FFMAX(1 - vLumFilterSize, vLumFilterPos[dstY]);
468  const int firstLumSrcY2 = FFMAX(1 - vLumFilterSize, vLumFilterPos[FFMIN(dstY | ((1 << c->chrDstVSubSample) - 1), dstH - 1)]);
469  // First line needed as input
470  const int firstChrSrcY = FFMAX(1 - vChrFilterSize, vChrFilterPos[chrDstY]);
471 
472  // Last line needed as input
473  int lastLumSrcY = FFMIN(c->srcH, firstLumSrcY + vLumFilterSize) - 1;
474  int lastLumSrcY2 = FFMIN(c->srcH, firstLumSrcY2 + vLumFilterSize) - 1;
475  int lastChrSrcY = FFMIN(c->chrSrcH, firstChrSrcY + vChrFilterSize) - 1;
476  int enough_lines;
477 
478  // handle holes (FAST_BILINEAR & weird filters)
479  if (firstLumSrcY > lastInLumBuf)
480  lastInLumBuf = firstLumSrcY - 1;
481  if (firstChrSrcY > lastInChrBuf)
482  lastInChrBuf = firstChrSrcY - 1;
483  av_assert0(firstLumSrcY >= lastInLumBuf - vLumBufSize + 1);
484  av_assert0(firstChrSrcY >= lastInChrBuf - vChrBufSize + 1);
485 
486  DEBUG_BUFFERS("dstY: %d\n", dstY);
487  DEBUG_BUFFERS("\tfirstLumSrcY: %d lastLumSrcY: %d lastInLumBuf: %d\n",
488  firstLumSrcY, lastLumSrcY, lastInLumBuf);
489  DEBUG_BUFFERS("\tfirstChrSrcY: %d lastChrSrcY: %d lastInChrBuf: %d\n",
490  firstChrSrcY, lastChrSrcY, lastInChrBuf);
491 
492  // Do we have enough lines in this slice to output the dstY line
493  enough_lines = lastLumSrcY2 < srcSliceY + srcSliceH &&
494  lastChrSrcY < FF_CEIL_RSHIFT(srcSliceY + srcSliceH, c->chrSrcVSubSample);
495 
496  if (!enough_lines) {
497  lastLumSrcY = srcSliceY + srcSliceH - 1;
498  lastChrSrcY = chrSrcSliceY + chrSrcSliceH - 1;
499  DEBUG_BUFFERS("buffering slice: lastLumSrcY %d lastChrSrcY %d\n",
500  lastLumSrcY, lastChrSrcY);
501  }
502 
503  // Do horizontal scaling
504  while (lastInLumBuf < lastLumSrcY) {
505  const uint8_t *src1[4] = {
506  src[0] + (lastInLumBuf + 1 - srcSliceY) * srcStride[0],
507  src[1] + (lastInLumBuf + 1 - srcSliceY) * srcStride[1],
508  src[2] + (lastInLumBuf + 1 - srcSliceY) * srcStride[2],
509  src[3] + (lastInLumBuf + 1 - srcSliceY) * srcStride[3],
510  };
511  lumBufIndex++;
512  av_assert0(lumBufIndex < 2 * vLumBufSize);
513  av_assert0(lastInLumBuf + 1 - srcSliceY < srcSliceH);
514  av_assert0(lastInLumBuf + 1 - srcSliceY >= 0);
515  hyscale(c, lumPixBuf[lumBufIndex], dstW, src1, srcW, lumXInc,
516  hLumFilter, hLumFilterPos, hLumFilterSize,
517  formatConvBuffer, pal, 0);
518  if (CONFIG_SWSCALE_ALPHA && alpPixBuf)
519  hyscale(c, alpPixBuf[lumBufIndex], dstW, src1, srcW,
520  lumXInc, hLumFilter, hLumFilterPos, hLumFilterSize,
521  formatConvBuffer, pal, 1);
522  lastInLumBuf++;
523  DEBUG_BUFFERS("\t\tlumBufIndex %d: lastInLumBuf: %d\n",
524  lumBufIndex, lastInLumBuf);
525  }
526  while (lastInChrBuf < lastChrSrcY) {
527  const uint8_t *src1[4] = {
528  src[0] + (lastInChrBuf + 1 - chrSrcSliceY) * srcStride[0],
529  src[1] + (lastInChrBuf + 1 - chrSrcSliceY) * srcStride[1],
530  src[2] + (lastInChrBuf + 1 - chrSrcSliceY) * srcStride[2],
531  src[3] + (lastInChrBuf + 1 - chrSrcSliceY) * srcStride[3],
532  };
533  chrBufIndex++;
534  av_assert0(chrBufIndex < 2 * vChrBufSize);
535  av_assert0(lastInChrBuf + 1 - chrSrcSliceY < (chrSrcSliceH));
536  av_assert0(lastInChrBuf + 1 - chrSrcSliceY >= 0);
537  // FIXME replace parameters through context struct (some at least)
538 
539  if (c->needs_hcscale)
540  hcscale(c, chrUPixBuf[chrBufIndex], chrVPixBuf[chrBufIndex],
541  chrDstW, src1, chrSrcW, chrXInc,
542  hChrFilter, hChrFilterPos, hChrFilterSize,
543  formatConvBuffer, pal);
544  lastInChrBuf++;
545  DEBUG_BUFFERS("\t\tchrBufIndex %d: lastInChrBuf: %d\n",
546  chrBufIndex, lastInChrBuf);
547  }
548  // wrap buf index around to stay inside the ring buffer
549  if (lumBufIndex >= vLumBufSize)
550  lumBufIndex -= vLumBufSize;
551  if (chrBufIndex >= vChrBufSize)
552  chrBufIndex -= vChrBufSize;
553  if (!enough_lines)
554  break; // we can't output a dstY line so let's try with the next slice
555 
556 #if HAVE_MMX_INLINE
557  updateMMXDitherTables(c, dstY, lumBufIndex, chrBufIndex,
558  lastInLumBuf, lastInChrBuf);
559 #endif
560  if (should_dither) {
561  c->chrDither8 = ff_dither_8x8_128[chrDstY & 7];
562  c->lumDither8 = ff_dither_8x8_128[dstY & 7];
563  }
564  if (dstY >= dstH - 2) {
565  /* hmm looks like we can't use MMX here without overwriting
566  * this array's tail */
567  ff_sws_init_output_funcs(c, &yuv2plane1, &yuv2planeX, &yuv2nv12cX,
568  &yuv2packed1, &yuv2packed2, &yuv2packedX, &yuv2anyX);
569  use_mmx_vfilter= 0;
570  }
571 
572  {
573  const int16_t **lumSrcPtr = (const int16_t **)(void*) lumPixBuf + lumBufIndex + firstLumSrcY - lastInLumBuf + vLumBufSize;
574  const int16_t **chrUSrcPtr = (const int16_t **)(void*) chrUPixBuf + chrBufIndex + firstChrSrcY - lastInChrBuf + vChrBufSize;
575  const int16_t **chrVSrcPtr = (const int16_t **)(void*) chrVPixBuf + chrBufIndex + firstChrSrcY - lastInChrBuf + vChrBufSize;
576  const int16_t **alpSrcPtr = (CONFIG_SWSCALE_ALPHA && alpPixBuf) ?
577  (const int16_t **)(void*) alpPixBuf + lumBufIndex + firstLumSrcY - lastInLumBuf + vLumBufSize : NULL;
578  int16_t *vLumFilter = c->vLumFilter;
579  int16_t *vChrFilter = c->vChrFilter;
580 
581  if (isPlanarYUV(dstFormat) ||
582  (isGray(dstFormat) && !isALPHA(dstFormat))) { // YV12 like
583  const int chrSkipMask = (1 << c->chrDstVSubSample) - 1;
584 
585  vLumFilter += dstY * vLumFilterSize;
586  vChrFilter += chrDstY * vChrFilterSize;
587 
588 // av_assert0(use_mmx_vfilter != (
589 // yuv2planeX == yuv2planeX_10BE_c
590 // || yuv2planeX == yuv2planeX_10LE_c
591 // || yuv2planeX == yuv2planeX_9BE_c
592 // || yuv2planeX == yuv2planeX_9LE_c
593 // || yuv2planeX == yuv2planeX_16BE_c
594 // || yuv2planeX == yuv2planeX_16LE_c
595 // || yuv2planeX == yuv2planeX_8_c) || !ARCH_X86);
596 
597  if(use_mmx_vfilter){
598  vLumFilter= (int16_t *)c->lumMmxFilter;
599  vChrFilter= (int16_t *)c->chrMmxFilter;
600  }
601 
602  if (vLumFilterSize == 1) {
603  yuv2plane1(lumSrcPtr[0], dest[0], dstW, c->lumDither8, 0);
604  } else {
605  yuv2planeX(vLumFilter, vLumFilterSize,
606  lumSrcPtr, dest[0],
607  dstW, c->lumDither8, 0);
608  }
609 
610  if (!((dstY & chrSkipMask) || isGray(dstFormat))) {
611  if (yuv2nv12cX) {
612  yuv2nv12cX(c, vChrFilter,
613  vChrFilterSize, chrUSrcPtr, chrVSrcPtr,
614  dest[1], chrDstW);
615  } else if (vChrFilterSize == 1) {
616  yuv2plane1(chrUSrcPtr[0], dest[1], chrDstW, c->chrDither8, 0);
617  yuv2plane1(chrVSrcPtr[0], dest[2], chrDstW, c->chrDither8, 3);
618  } else {
619  yuv2planeX(vChrFilter,
620  vChrFilterSize, chrUSrcPtr, dest[1],
621  chrDstW, c->chrDither8, 0);
622  yuv2planeX(vChrFilter,
623  vChrFilterSize, chrVSrcPtr, dest[2],
624  chrDstW, c->chrDither8, use_mmx_vfilter ? (c->uv_offx2 >> 1) : 3);
625  }
626  }
627 
628  if (CONFIG_SWSCALE_ALPHA && alpPixBuf) {
629  if(use_mmx_vfilter){
630  vLumFilter= (int16_t *)c->alpMmxFilter;
631  }
632  if (vLumFilterSize == 1) {
633  yuv2plane1(alpSrcPtr[0], dest[3], dstW,
634  c->lumDither8, 0);
635  } else {
636  yuv2planeX(vLumFilter,
637  vLumFilterSize, alpSrcPtr, dest[3],
638  dstW, c->lumDither8, 0);
639  }
640  }
641  } else if (yuv2packedX) {
642  av_assert1(lumSrcPtr + vLumFilterSize - 1 < (const int16_t **)lumPixBuf + vLumBufSize * 2);
643  av_assert1(chrUSrcPtr + vChrFilterSize - 1 < (const int16_t **)chrUPixBuf + vChrBufSize * 2);
644  if (c->yuv2packed1 && vLumFilterSize == 1 &&
645  vChrFilterSize <= 2) { // unscaled RGB
646  int chrAlpha = vChrFilterSize == 1 ? 0 : vChrFilter[2 * dstY + 1];
647  yuv2packed1(c, *lumSrcPtr, chrUSrcPtr, chrVSrcPtr,
648  alpPixBuf ? *alpSrcPtr : NULL,
649  dest[0], dstW, chrAlpha, dstY);
650  } else if (c->yuv2packed2 && vLumFilterSize == 2 &&
651  vChrFilterSize == 2) { // bilinear upscale RGB
652  int lumAlpha = vLumFilter[2 * dstY + 1];
653  int chrAlpha = vChrFilter[2 * dstY + 1];
654  lumMmxFilter[2] =
655  lumMmxFilter[3] = vLumFilter[2 * dstY] * 0x10001;
656  chrMmxFilter[2] =
657  chrMmxFilter[3] = vChrFilter[2 * chrDstY] * 0x10001;
658  yuv2packed2(c, lumSrcPtr, chrUSrcPtr, chrVSrcPtr,
659  alpPixBuf ? alpSrcPtr : NULL,
660  dest[0], dstW, lumAlpha, chrAlpha, dstY);
661  } else { // general RGB
662  yuv2packedX(c, vLumFilter + dstY * vLumFilterSize,
663  lumSrcPtr, vLumFilterSize,
664  vChrFilter + dstY * vChrFilterSize,
665  chrUSrcPtr, chrVSrcPtr, vChrFilterSize,
666  alpSrcPtr, dest[0], dstW, dstY);
667  }
668  } else {
669  av_assert1(!yuv2packed1 && !yuv2packed2);
670  yuv2anyX(c, vLumFilter + dstY * vLumFilterSize,
671  lumSrcPtr, vLumFilterSize,
672  vChrFilter + dstY * vChrFilterSize,
673  chrUSrcPtr, chrVSrcPtr, vChrFilterSize,
674  alpSrcPtr, dest, dstW, dstY);
675  }
676  }
677  }
678  if (isPlanar(dstFormat) && isALPHA(dstFormat) && !alpPixBuf) {
679  int length = dstW;
680  int height = dstY - lastDstY;
681 
682  if (is16BPS(dstFormat) || isNBPS(dstFormat)) {
683  const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(dstFormat);
684  fillPlane16(dst[3], dstStride[3], length, height, lastDstY,
685  1, desc->comp[3].depth_minus1,
686  isBE(dstFormat));
687  } else
688  fillPlane(dst[3], dstStride[3], length, height, lastDstY, 255);
689  }
690 
691 #if HAVE_MMXEXT_INLINE
693  __asm__ volatile ("sfence" ::: "memory");
694 #endif
695  emms_c();
696 
697  /* store changed local vars back in the context */
698  c->dstY = dstY;
703 
704  return dstY - lastDstY;
705 }
706 
708 {
710 
712  &c->yuv2nv12cX, &c->yuv2packed1,
713  &c->yuv2packed2, &c->yuv2packedX, &c->yuv2anyX);
714 
716 
717 
718  if (c->srcBpc == 8) {
719  if (c->dstBpc <= 14) {
720  c->hyScale = c->hcScale = hScale8To15_c;
721  if (c->flags & SWS_FAST_BILINEAR) {
724  }
725  } else {
726  c->hyScale = c->hcScale = hScale8To19_c;
727  }
728  } else {
729  c->hyScale = c->hcScale = c->dstBpc > 14 ? hScale16To19_c
730  : hScale16To15_c;
731  }
732 
733  if (c->srcRange != c->dstRange && !isAnyRGB(c->dstFormat)) {
734  if (c->dstBpc <= 14) {
735  if (c->srcRange) {
738  } else {
741  }
742  } else {
743  if (c->srcRange) {
746  } else {
749  }
750  }
751  }
752 
753  if (!(isGray(srcFormat) || isGray(c->dstFormat) ||
754  srcFormat == AV_PIX_FMT_MONOBLACK || srcFormat == AV_PIX_FMT_MONOWHITE))
755  c->needs_hcscale = 1;
756 }
757 
759 {
760  sws_init_swscale(c);
761 
762  if (ARCH_PPC)
764  if (ARCH_X86)
766 
767  return swscale;
768 }
769 
770 static void reset_ptr(const uint8_t *src[], int format)
771 {
772  if (!isALPHA(format))
773  src[3] = NULL;
774  if (!isPlanar(format)) {
775  src[3] = src[2] = NULL;
776 
777  if (!usePal(format))
778  src[1] = NULL;
779  }
780 }
781 
782 static int check_image_pointers(const uint8_t * const data[4], enum AVPixelFormat pix_fmt,
783  const int linesizes[4])
784 {
785  const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(pix_fmt);
786  int i;
787 
788  for (i = 0; i < 4; i++) {
789  int plane = desc->comp[i].plane;
790  if (!data[plane] || !linesizes[plane])
791  return 0;
792  }
793 
794  return 1;
795 }
796 
797 static void xyz12Torgb48(struct SwsContext *c, uint16_t *dst,
798  const uint16_t *src, int stride, int h)
799 {
800  int xp,yp;
802 
803  for (yp=0; yp<h; yp++) {
804  for (xp=0; xp+2<stride; xp+=3) {
805  int x, y, z, r, g, b;
806 
807  if (desc->flags & AV_PIX_FMT_FLAG_BE) {
808  x = AV_RB16(src + xp + 0);
809  y = AV_RB16(src + xp + 1);
810  z = AV_RB16(src + xp + 2);
811  } else {
812  x = AV_RL16(src + xp + 0);
813  y = AV_RL16(src + xp + 1);
814  z = AV_RL16(src + xp + 2);
815  }
816 
817  x = c->xyzgamma[x>>4];
818  y = c->xyzgamma[y>>4];
819  z = c->xyzgamma[z>>4];
820 
821  // convert from XYZlinear to sRGBlinear
822  r = c->xyz2rgb_matrix[0][0] * x +
823  c->xyz2rgb_matrix[0][1] * y +
824  c->xyz2rgb_matrix[0][2] * z >> 12;
825  g = c->xyz2rgb_matrix[1][0] * x +
826  c->xyz2rgb_matrix[1][1] * y +
827  c->xyz2rgb_matrix[1][2] * z >> 12;
828  b = c->xyz2rgb_matrix[2][0] * x +
829  c->xyz2rgb_matrix[2][1] * y +
830  c->xyz2rgb_matrix[2][2] * z >> 12;
831 
832  // limit values to 12-bit depth
833  r = av_clip_c(r,0,4095);
834  g = av_clip_c(g,0,4095);
835  b = av_clip_c(b,0,4095);
836 
837  // convert from sRGBlinear to RGB and scale from 12bit to 16bit
838  if (desc->flags & AV_PIX_FMT_FLAG_BE) {
839  AV_WB16(dst + xp + 0, c->rgbgamma[r] << 4);
840  AV_WB16(dst + xp + 1, c->rgbgamma[g] << 4);
841  AV_WB16(dst + xp + 2, c->rgbgamma[b] << 4);
842  } else {
843  AV_WL16(dst + xp + 0, c->rgbgamma[r] << 4);
844  AV_WL16(dst + xp + 1, c->rgbgamma[g] << 4);
845  AV_WL16(dst + xp + 2, c->rgbgamma[b] << 4);
846  }
847  }
848  src += stride;
849  dst += stride;
850  }
851 }
852 
853 static void rgb48Toxyz12(struct SwsContext *c, uint16_t *dst,
854  const uint16_t *src, int stride, int h)
855 {
856  int xp,yp;
858 
859  for (yp=0; yp<h; yp++) {
860  for (xp=0; xp+2<stride; xp+=3) {
861  int x, y, z, r, g, b;
862 
863  if (desc->flags & AV_PIX_FMT_FLAG_BE) {
864  r = AV_RB16(src + xp + 0);
865  g = AV_RB16(src + xp + 1);
866  b = AV_RB16(src + xp + 2);
867  } else {
868  r = AV_RL16(src + xp + 0);
869  g = AV_RL16(src + xp + 1);
870  b = AV_RL16(src + xp + 2);
871  }
872 
873  r = c->rgbgammainv[r>>4];
874  g = c->rgbgammainv[g>>4];
875  b = c->rgbgammainv[b>>4];
876 
877  // convert from sRGBlinear to XYZlinear
878  x = c->rgb2xyz_matrix[0][0] * r +
879  c->rgb2xyz_matrix[0][1] * g +
880  c->rgb2xyz_matrix[0][2] * b >> 12;
881  y = c->rgb2xyz_matrix[1][0] * r +
882  c->rgb2xyz_matrix[1][1] * g +
883  c->rgb2xyz_matrix[1][2] * b >> 12;
884  z = c->rgb2xyz_matrix[2][0] * r +
885  c->rgb2xyz_matrix[2][1] * g +
886  c->rgb2xyz_matrix[2][2] * b >> 12;
887 
888  // limit values to 12-bit depth
889  x = av_clip_c(x,0,4095);
890  y = av_clip_c(y,0,4095);
891  z = av_clip_c(z,0,4095);
892 
893  // convert from XYZlinear to X'Y'Z' and scale from 12bit to 16bit
894  if (desc->flags & AV_PIX_FMT_FLAG_BE) {
895  AV_WB16(dst + xp + 0, c->xyzgammainv[x] << 4);
896  AV_WB16(dst + xp + 1, c->xyzgammainv[y] << 4);
897  AV_WB16(dst + xp + 2, c->xyzgammainv[z] << 4);
898  } else {
899  AV_WL16(dst + xp + 0, c->xyzgammainv[x] << 4);
900  AV_WL16(dst + xp + 1, c->xyzgammainv[y] << 4);
901  AV_WL16(dst + xp + 2, c->xyzgammainv[z] << 4);
902  }
903  }
904  src += stride;
905  dst += stride;
906  }
907 }
908 
909 /**
910  * swscale wrapper, so we don't need to export the SwsContext.
911  * Assumes planar YUV to be in YUV order instead of YVU.
912  */
914  const uint8_t * const srcSlice[],
915  const int srcStride[], int srcSliceY,
916  int srcSliceH, uint8_t *const dst[],
917  const int dstStride[])
918 {
919  int i, ret;
920  const uint8_t *src2[4];
921  uint8_t *dst2[4];
922  uint8_t *rgb0_tmp = NULL;
923 
924  if (!srcSlice || !dstStride || !dst || !srcSlice) {
925  av_log(c, AV_LOG_ERROR, "One of the input parameters to sws_scale() is NULL, please check the calling code\n");
926  return 0;
927  }
928  memcpy(src2, srcSlice, sizeof(src2));
929  memcpy(dst2, dst, sizeof(dst2));
930 
931  // do not mess up sliceDir if we have a "trailing" 0-size slice
932  if (srcSliceH == 0)
933  return 0;
934 
935  if (!check_image_pointers(srcSlice, c->srcFormat, srcStride)) {
936  av_log(c, AV_LOG_ERROR, "bad src image pointers\n");
937  return 0;
938  }
939  if (!check_image_pointers((const uint8_t* const*)dst, c->dstFormat, dstStride)) {
940  av_log(c, AV_LOG_ERROR, "bad dst image pointers\n");
941  return 0;
942  }
943 
944  if (c->sliceDir == 0 && srcSliceY != 0 && srcSliceY + srcSliceH != c->srcH) {
945  av_log(c, AV_LOG_ERROR, "Slices start in the middle!\n");
946  return 0;
947  }
948  if (c->sliceDir == 0) {
949  if (srcSliceY == 0) c->sliceDir = 1; else c->sliceDir = -1;
950  }
951 
952  if (usePal(c->srcFormat)) {
953  for (i = 0; i < 256; i++) {
954  int p, r, g, b, y, u, v, a = 0xff;
955  if (c->srcFormat == AV_PIX_FMT_PAL8) {
956  p = ((const uint32_t *)(srcSlice[1]))[i];
957  a = (p >> 24) & 0xFF;
958  r = (p >> 16) & 0xFF;
959  g = (p >> 8) & 0xFF;
960  b = p & 0xFF;
961  } else if (c->srcFormat == AV_PIX_FMT_RGB8) {
962  r = ( i >> 5 ) * 36;
963  g = ((i >> 2) & 7) * 36;
964  b = ( i & 3) * 85;
965  } else if (c->srcFormat == AV_PIX_FMT_BGR8) {
966  b = ( i >> 6 ) * 85;
967  g = ((i >> 3) & 7) * 36;
968  r = ( i & 7) * 36;
969  } else if (c->srcFormat == AV_PIX_FMT_RGB4_BYTE) {
970  r = ( i >> 3 ) * 255;
971  g = ((i >> 1) & 3) * 85;
972  b = ( i & 1) * 255;
973  } else if (c->srcFormat == AV_PIX_FMT_GRAY8 || c->srcFormat == AV_PIX_FMT_GRAY8A) {
974  r = g = b = i;
975  } else {
977  b = ( i >> 3 ) * 255;
978  g = ((i >> 1) & 3) * 85;
979  r = ( i & 1) * 255;
980  }
981 #define RGB2YUV_SHIFT 15
982 #define BY ( (int) (0.114 * 219 / 255 * (1 << RGB2YUV_SHIFT) + 0.5))
983 #define BV (-(int) (0.081 * 224 / 255 * (1 << RGB2YUV_SHIFT) + 0.5))
984 #define BU ( (int) (0.500 * 224 / 255 * (1 << RGB2YUV_SHIFT) + 0.5))
985 #define GY ( (int) (0.587 * 219 / 255 * (1 << RGB2YUV_SHIFT) + 0.5))
986 #define GV (-(int) (0.419 * 224 / 255 * (1 << RGB2YUV_SHIFT) + 0.5))
987 #define GU (-(int) (0.331 * 224 / 255 * (1 << RGB2YUV_SHIFT) + 0.5))
988 #define RY ( (int) (0.299 * 219 / 255 * (1 << RGB2YUV_SHIFT) + 0.5))
989 #define RV ( (int) (0.500 * 224 / 255 * (1 << RGB2YUV_SHIFT) + 0.5))
990 #define RU (-(int) (0.169 * 224 / 255 * (1 << RGB2YUV_SHIFT) + 0.5))
991 
992  y = av_clip_uint8((RY * r + GY * g + BY * b + ( 33 << (RGB2YUV_SHIFT - 1))) >> RGB2YUV_SHIFT);
993  u = av_clip_uint8((RU * r + GU * g + BU * b + (257 << (RGB2YUV_SHIFT - 1))) >> RGB2YUV_SHIFT);
994  v = av_clip_uint8((RV * r + GV * g + BV * b + (257 << (RGB2YUV_SHIFT - 1))) >> RGB2YUV_SHIFT);
995  c->pal_yuv[i]= y + (u<<8) + (v<<16) + ((unsigned)a<<24);
996 
997  switch (c->dstFormat) {
998  case AV_PIX_FMT_BGR32:
999 #if !HAVE_BIGENDIAN
1000  case AV_PIX_FMT_RGB24:
1001 #endif
1002  c->pal_rgb[i]= r + (g<<8) + (b<<16) + ((unsigned)a<<24);
1003  break;
1004  case AV_PIX_FMT_BGR32_1:
1005 #if HAVE_BIGENDIAN
1006  case AV_PIX_FMT_BGR24:
1007 #endif
1008  c->pal_rgb[i]= a + (r<<8) + (g<<16) + ((unsigned)b<<24);
1009  break;
1010  case AV_PIX_FMT_RGB32_1:
1011 #if HAVE_BIGENDIAN
1012  case AV_PIX_FMT_RGB24:
1013 #endif
1014  c->pal_rgb[i]= a + (b<<8) + (g<<16) + ((unsigned)r<<24);
1015  break;
1016  case AV_PIX_FMT_RGB32:
1017 #if !HAVE_BIGENDIAN
1018  case AV_PIX_FMT_BGR24:
1019 #endif
1020  default:
1021  c->pal_rgb[i]= b + (g<<8) + (r<<16) + ((unsigned)a<<24);
1022  }
1023  }
1024  }
1025 
1026  if (c->src0Alpha && !c->dst0Alpha && isALPHA(c->dstFormat)) {
1027  uint8_t *base;
1028  int x,y;
1029  rgb0_tmp = av_malloc(FFABS(srcStride[0]) * srcSliceH + 32);
1030  if (!rgb0_tmp)
1031  return AVERROR(ENOMEM);
1032 
1033  base = srcStride[0] < 0 ? rgb0_tmp - srcStride[0] * (srcSliceH-1) : rgb0_tmp;
1034  for (y=0; y<srcSliceH; y++){
1035  memcpy(base + srcStride[0]*y, src2[0] + srcStride[0]*y, 4*c->srcW);
1036  for (x=c->src0Alpha-1; x<4*c->srcW; x+=4) {
1037  base[ srcStride[0]*y + x] = 0xFF;
1038  }
1039  }
1040  src2[0] = base;
1041  }
1042 
1043  if (c->srcXYZ && !(c->dstXYZ && c->srcW==c->dstW && c->srcH==c->dstH)) {
1044  uint8_t *base;
1045  rgb0_tmp = av_malloc(FFABS(srcStride[0]) * srcSliceH + 32);
1046  if (!rgb0_tmp)
1047  return AVERROR(ENOMEM);
1048 
1049  base = srcStride[0] < 0 ? rgb0_tmp - srcStride[0] * (srcSliceH-1) : rgb0_tmp;
1050 
1051  xyz12Torgb48(c, (uint16_t*)base, (const uint16_t*)src2[0], srcStride[0]/2, srcSliceH);
1052  src2[0] = base;
1053  }
1054 
1055  if (!srcSliceY && (c->flags & SWS_BITEXACT) && c->dither == SWS_DITHER_ED && c->dither_error[0])
1056  for (i = 0; i < 4; i++)
1057  memset(c->dither_error[i], 0, sizeof(c->dither_error[0][0]) * (c->dstW+2));
1058 
1059 
1060  // copy strides, so they can safely be modified
1061  if (c->sliceDir == 1) {
1062  // slices go from top to bottom
1063  int srcStride2[4] = { srcStride[0], srcStride[1], srcStride[2],
1064  srcStride[3] };
1065  int dstStride2[4] = { dstStride[0], dstStride[1], dstStride[2],
1066  dstStride[3] };
1067 
1068  reset_ptr(src2, c->srcFormat);
1069  reset_ptr((void*)dst2, c->dstFormat);
1070 
1071  /* reset slice direction at end of frame */
1072  if (srcSliceY + srcSliceH == c->srcH)
1073  c->sliceDir = 0;
1074 
1075  ret = c->swscale(c, src2, srcStride2, srcSliceY, srcSliceH, dst2,
1076  dstStride2);
1077  } else {
1078  // slices go from bottom to top => we flip the image internally
1079  int srcStride2[4] = { -srcStride[0], -srcStride[1], -srcStride[2],
1080  -srcStride[3] };
1081  int dstStride2[4] = { -dstStride[0], -dstStride[1], -dstStride[2],
1082  -dstStride[3] };
1083 
1084  src2[0] += (srcSliceH - 1) * srcStride[0];
1085  if (!usePal(c->srcFormat))
1086  src2[1] += ((srcSliceH >> c->chrSrcVSubSample) - 1) * srcStride[1];
1087  src2[2] += ((srcSliceH >> c->chrSrcVSubSample) - 1) * srcStride[2];
1088  src2[3] += (srcSliceH - 1) * srcStride[3];
1089  dst2[0] += ( c->dstH - 1) * dstStride[0];
1090  dst2[1] += ((c->dstH >> c->chrDstVSubSample) - 1) * dstStride[1];
1091  dst2[2] += ((c->dstH >> c->chrDstVSubSample) - 1) * dstStride[2];
1092  dst2[3] += ( c->dstH - 1) * dstStride[3];
1093 
1094  reset_ptr(src2, c->srcFormat);
1095  reset_ptr((void*)dst2, c->dstFormat);
1096 
1097  /* reset slice direction at end of frame */
1098  if (!srcSliceY)
1099  c->sliceDir = 0;
1100 
1101  ret = c->swscale(c, src2, srcStride2, c->srcH-srcSliceY-srcSliceH,
1102  srcSliceH, dst2, dstStride2);
1103  }
1104 
1105 
1106  if (c->dstXYZ && !(c->srcXYZ && c->srcW==c->dstW && c->srcH==c->dstH)) {
1107  /* replace on the same data */
1108  rgb48Toxyz12(c, (uint16_t*)dst2[0], (const uint16_t*)dst2[0], dstStride[0]/2, ret);
1109  }
1110 
1111  av_free(rgb0_tmp);
1112  return ret;
1113 }
1114