ffmpeg/libswscale/swscale.c

1252 lines
44 KiB
C

/*
* Copyright (C) 2001-2011 Michael Niedermayer <michaelni@gmx.at>
*
* This file is part of FFmpeg.
*
* FFmpeg is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* FFmpeg is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include <stdint.h>
#include <stdio.h>
#include <string.h>
#include "libavutil/avassert.h"
#include "libavutil/bswap.h"
#include "libavutil/common.h"
#include "libavutil/cpu.h"
#include "libavutil/emms.h"
#include "libavutil/intreadwrite.h"
#include "libavutil/mem.h"
#include "libavutil/mem_internal.h"
#include "libavutil/pixdesc.h"
#include "config.h"
#include "swscale_internal.h"
#include "swscale.h"
DECLARE_ALIGNED(8, const uint8_t, ff_dither_8x8_128)[9][8] = {
{ 36, 68, 60, 92, 34, 66, 58, 90, },
{ 100, 4, 124, 28, 98, 2, 122, 26, },
{ 52, 84, 44, 76, 50, 82, 42, 74, },
{ 116, 20, 108, 12, 114, 18, 106, 10, },
{ 32, 64, 56, 88, 38, 70, 62, 94, },
{ 96, 0, 120, 24, 102, 6, 126, 30, },
{ 48, 80, 40, 72, 54, 86, 46, 78, },
{ 112, 16, 104, 8, 118, 22, 110, 14, },
{ 36, 68, 60, 92, 34, 66, 58, 90, },
};
DECLARE_ALIGNED(8, static const uint8_t, sws_pb_64)[8] = {
64, 64, 64, 64, 64, 64, 64, 64
};
static av_always_inline void fillPlane(uint8_t *plane, int stride, int width,
int height, int y, uint8_t val)
{
int i;
uint8_t *ptr = plane + stride * y;
for (i = 0; i < height; i++) {
memset(ptr, val, width);
ptr += stride;
}
}
static void hScale16To19_c(SwsContext *c, int16_t *_dst, int dstW,
const uint8_t *_src, const int16_t *filter,
const int32_t *filterPos, int filterSize)
{
const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(c->srcFormat);
int i;
int32_t *dst = (int32_t *) _dst;
const uint16_t *src = (const uint16_t *) _src;
int bits = desc->comp[0].depth - 1;
int sh = bits - 4;
if ((isAnyRGB(c->srcFormat) || c->srcFormat==AV_PIX_FMT_PAL8) && desc->comp[0].depth<16) {
sh = 9;
} else if (desc->flags & AV_PIX_FMT_FLAG_FLOAT) { /* float input are process like uint 16bpc */
sh = 16 - 1 - 4;
}
for (i = 0; i < dstW; i++) {
int j;
int srcPos = filterPos[i];
int val = 0;
for (j = 0; j < filterSize; j++) {
val += src[srcPos + j] * filter[filterSize * i + j];
}
// filter=14 bit, input=16 bit, output=30 bit, >> 11 makes 19 bit
dst[i] = FFMIN(val >> sh, (1 << 19) - 1);
}
}
static void hScale16To15_c(SwsContext *c, int16_t *dst, int dstW,
const uint8_t *_src, const int16_t *filter,
const int32_t *filterPos, int filterSize)
{
const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(c->srcFormat);
int i;
const uint16_t *src = (const uint16_t *) _src;
int sh = desc->comp[0].depth - 1;
if (sh<15) {
sh = isAnyRGB(c->srcFormat) || c->srcFormat==AV_PIX_FMT_PAL8 ? 13 : (desc->comp[0].depth - 1);
} else if (desc->flags & AV_PIX_FMT_FLAG_FLOAT) { /* float input are process like uint 16bpc */
sh = 16 - 1;
}
for (i = 0; i < dstW; i++) {
int j;
int srcPos = filterPos[i];
int val = 0;
for (j = 0; j < filterSize; j++) {
val += src[srcPos + j] * filter[filterSize * i + j];
}
// filter=14 bit, input=16 bit, output=30 bit, >> 15 makes 15 bit
dst[i] = FFMIN(val >> sh, (1 << 15) - 1);
}
}
// bilinear / bicubic scaling
static void hScale8To15_c(SwsContext *c, int16_t *dst, int dstW,
const uint8_t *src, const int16_t *filter,
const int32_t *filterPos, int filterSize)
{
int i;
for (i = 0; i < dstW; i++) {
int j;
int srcPos = filterPos[i];
int val = 0;
for (j = 0; j < filterSize; j++) {
val += ((int)src[srcPos + j]) * filter[filterSize * i + j];
}
dst[i] = FFMIN(val >> 7, (1 << 15) - 1); // the cubic equation does overflow ...
}
}
static void hScale8To19_c(SwsContext *c, int16_t *_dst, int dstW,
const uint8_t *src, const int16_t *filter,
const int32_t *filterPos, int filterSize)
{
int i;
int32_t *dst = (int32_t *) _dst;
for (i = 0; i < dstW; i++) {
int j;
int srcPos = filterPos[i];
int val = 0;
for (j = 0; j < filterSize; j++) {
val += ((int)src[srcPos + j]) * filter[filterSize * i + j];
}
dst[i] = FFMIN(val >> 3, (1 << 19) - 1); // the cubic equation does overflow ...
}
}
// FIXME all pal and rgb srcFormats could do this conversion as well
// FIXME all scalers more complex than bilinear could do half of this transform
static void chrRangeToJpeg_c(int16_t *dstU, int16_t *dstV, int width)
{
int i;
for (i = 0; i < width; i++) {
dstU[i] = (FFMIN(dstU[i], 30775) * 4663 - 9289992) >> 12; // -264
dstV[i] = (FFMIN(dstV[i], 30775) * 4663 - 9289992) >> 12; // -264
}
}
static void chrRangeFromJpeg_c(int16_t *dstU, int16_t *dstV, int width)
{
int i;
for (i = 0; i < width; i++) {
dstU[i] = (dstU[i] * 1799 + 4081085) >> 11; // 1469
dstV[i] = (dstV[i] * 1799 + 4081085) >> 11; // 1469
}
}
static void lumRangeToJpeg_c(int16_t *dst, int width)
{
int i;
for (i = 0; i < width; i++)
dst[i] = (FFMIN(dst[i], 30189) * 19077 - 39057361) >> 14;
}
static void lumRangeFromJpeg_c(int16_t *dst, int width)
{
int i;
for (i = 0; i < width; i++)
dst[i] = (dst[i] * 14071 + 33561947) >> 14;
}
static void chrRangeToJpeg16_c(int16_t *_dstU, int16_t *_dstV, int width)
{
int i;
int32_t *dstU = (int32_t *) _dstU;
int32_t *dstV = (int32_t *) _dstV;
for (i = 0; i < width; i++) {
dstU[i] = (FFMIN(dstU[i], 30775 << 4) * 4663 - (9289992 << 4)) >> 12; // -264
dstV[i] = (FFMIN(dstV[i], 30775 << 4) * 4663 - (9289992 << 4)) >> 12; // -264
}
}
static void chrRangeFromJpeg16_c(int16_t *_dstU, int16_t *_dstV, int width)
{
int i;
int32_t *dstU = (int32_t *) _dstU;
int32_t *dstV = (int32_t *) _dstV;
for (i = 0; i < width; i++) {
dstU[i] = (dstU[i] * 1799 + (4081085 << 4)) >> 11; // 1469
dstV[i] = (dstV[i] * 1799 + (4081085 << 4)) >> 11; // 1469
}
}
static void lumRangeToJpeg16_c(int16_t *_dst, int width)
{
int i;
int32_t *dst = (int32_t *) _dst;
for (i = 0; i < width; i++) {
dst[i] = ((int)(FFMIN(dst[i], 30189 << 4) * 4769U - (39057361 << 2))) >> 12;
}
}
static void lumRangeFromJpeg16_c(int16_t *_dst, int width)
{
int i;
int32_t *dst = (int32_t *) _dst;
for (i = 0; i < width; i++)
dst[i] = (dst[i]*(14071/4) + (33561947<<4)/4)>>12;
}
#define DEBUG_SWSCALE_BUFFERS 0
#define DEBUG_BUFFERS(...) \
if (DEBUG_SWSCALE_BUFFERS) \
av_log(c, AV_LOG_DEBUG, __VA_ARGS__)
static int swscale(SwsContext *c, const uint8_t *src[],
int srcStride[], int srcSliceY, int srcSliceH,
uint8_t *dst[], int dstStride[],
int dstSliceY, int dstSliceH)
{
const int scale_dst = dstSliceY > 0 || dstSliceH < c->dstH;
/* load a few things into local vars to make the code more readable?
* and faster */
const int dstW = c->dstW;
int dstH = c->dstH;
const enum AVPixelFormat dstFormat = c->dstFormat;
const int flags = c->flags;
int32_t *vLumFilterPos = c->vLumFilterPos;
int32_t *vChrFilterPos = c->vChrFilterPos;
const int vLumFilterSize = c->vLumFilterSize;
const int vChrFilterSize = c->vChrFilterSize;
yuv2planar1_fn yuv2plane1 = c->yuv2plane1;
yuv2planarX_fn yuv2planeX = c->yuv2planeX;
yuv2interleavedX_fn yuv2nv12cX = c->yuv2nv12cX;
yuv2packed1_fn yuv2packed1 = c->yuv2packed1;
yuv2packed2_fn yuv2packed2 = c->yuv2packed2;
yuv2packedX_fn yuv2packedX = c->yuv2packedX;
yuv2anyX_fn yuv2anyX = c->yuv2anyX;
const int chrSrcSliceY = srcSliceY >> c->chrSrcVSubSample;
const int chrSrcSliceH = AV_CEIL_RSHIFT(srcSliceH, c->chrSrcVSubSample);
int should_dither = isNBPS(c->srcFormat) ||
is16BPS(c->srcFormat);
int lastDstY;
/* vars which will change and which we need to store back in the context */
int dstY = c->dstY;
int lastInLumBuf = c->lastInLumBuf;
int lastInChrBuf = c->lastInChrBuf;
int lumStart = 0;
int lumEnd = c->descIndex[0];
int chrStart = lumEnd;
int chrEnd = c->descIndex[1];
int vStart = chrEnd;
int vEnd = c->numDesc;
SwsSlice *src_slice = &c->slice[lumStart];
SwsSlice *hout_slice = &c->slice[c->numSlice-2];
SwsSlice *vout_slice = &c->slice[c->numSlice-1];
SwsFilterDescriptor *desc = c->desc;
int needAlpha = c->needAlpha;
int hasLumHoles = 1;
int hasChrHoles = 1;
if (isPacked(c->srcFormat)) {
src[1] =
src[2] =
src[3] = src[0];
srcStride[1] =
srcStride[2] =
srcStride[3] = srcStride[0];
}
srcStride[1] *= 1 << c->vChrDrop;
srcStride[2] *= 1 << c->vChrDrop;
DEBUG_BUFFERS("swscale() %p[%d] %p[%d] %p[%d] %p[%d] -> %p[%d] %p[%d] %p[%d] %p[%d]\n",
src[0], srcStride[0], src[1], srcStride[1],
src[2], srcStride[2], src[3], srcStride[3],
dst[0], dstStride[0], dst[1], dstStride[1],
dst[2], dstStride[2], dst[3], dstStride[3]);
DEBUG_BUFFERS("srcSliceY: %d srcSliceH: %d dstY: %d dstH: %d\n",
srcSliceY, srcSliceH, dstY, dstH);
DEBUG_BUFFERS("vLumFilterSize: %d vChrFilterSize: %d\n",
vLumFilterSize, vChrFilterSize);
if (dstStride[0]&15 || dstStride[1]&15 ||
dstStride[2]&15 || dstStride[3]&15) {
SwsContext *const ctx = c->parent ? c->parent : c;
if (flags & SWS_PRINT_INFO &&
!atomic_exchange_explicit(&ctx->stride_unaligned_warned, 1, memory_order_relaxed)) {
av_log(c, AV_LOG_WARNING,
"Warning: dstStride is not aligned!\n"
" ->cannot do aligned memory accesses anymore\n");
}
}
#if ARCH_X86
if ( (uintptr_t)dst[0]&15 || (uintptr_t)dst[1]&15 || (uintptr_t)dst[2]&15
|| (uintptr_t)src[0]&15 || (uintptr_t)src[1]&15 || (uintptr_t)src[2]&15
|| dstStride[0]&15 || dstStride[1]&15 || dstStride[2]&15 || dstStride[3]&15
|| srcStride[0]&15 || srcStride[1]&15 || srcStride[2]&15 || srcStride[3]&15
) {
SwsContext *const ctx = c->parent ? c->parent : c;
int cpu_flags = av_get_cpu_flags();
if (flags & SWS_PRINT_INFO && HAVE_MMXEXT && (cpu_flags & AV_CPU_FLAG_SSE2) &&
!atomic_exchange_explicit(&ctx->stride_unaligned_warned,1, memory_order_relaxed)) {
av_log(c, AV_LOG_WARNING, "Warning: data is not aligned! This can lead to a speed loss\n");
}
}
#endif
if (scale_dst) {
dstY = dstSliceY;
dstH = dstY + dstSliceH;
lastInLumBuf = -1;
lastInChrBuf = -1;
} else if (srcSliceY == 0) {
/* Note the user might start scaling the picture in the middle so this
* will not get executed. This is not really intended but works
* currently, so people might do it. */
dstY = 0;
lastInLumBuf = -1;
lastInChrBuf = -1;
}
if (!should_dither) {
c->chrDither8 = c->lumDither8 = sws_pb_64;
}
lastDstY = dstY;
ff_init_vscale_pfn(c, yuv2plane1, yuv2planeX, yuv2nv12cX,
yuv2packed1, yuv2packed2, yuv2packedX, yuv2anyX, c->use_mmx_vfilter);
ff_init_slice_from_src(src_slice, (uint8_t**)src, srcStride, c->srcW,
srcSliceY, srcSliceH, chrSrcSliceY, chrSrcSliceH, 1);
ff_init_slice_from_src(vout_slice, (uint8_t**)dst, dstStride, c->dstW,
dstY, dstSliceH, dstY >> c->chrDstVSubSample,
AV_CEIL_RSHIFT(dstSliceH, c->chrDstVSubSample), scale_dst);
if (srcSliceY == 0) {
hout_slice->plane[0].sliceY = lastInLumBuf + 1;
hout_slice->plane[1].sliceY = lastInChrBuf + 1;
hout_slice->plane[2].sliceY = lastInChrBuf + 1;
hout_slice->plane[3].sliceY = lastInLumBuf + 1;
hout_slice->plane[0].sliceH =
hout_slice->plane[1].sliceH =
hout_slice->plane[2].sliceH =
hout_slice->plane[3].sliceH = 0;
hout_slice->width = dstW;
}
for (; dstY < dstH; dstY++) {
const int chrDstY = dstY >> c->chrDstVSubSample;
int use_mmx_vfilter= c->use_mmx_vfilter;
// First line needed as input
const int firstLumSrcY = FFMAX(1 - vLumFilterSize, vLumFilterPos[dstY]);
const int firstLumSrcY2 = FFMAX(1 - vLumFilterSize, vLumFilterPos[FFMIN(dstY | ((1 << c->chrDstVSubSample) - 1), c->dstH - 1)]);
// First line needed as input
const int firstChrSrcY = FFMAX(1 - vChrFilterSize, vChrFilterPos[chrDstY]);
// Last line needed as input
int lastLumSrcY = FFMIN(c->srcH, firstLumSrcY + vLumFilterSize) - 1;
int lastLumSrcY2 = FFMIN(c->srcH, firstLumSrcY2 + vLumFilterSize) - 1;
int lastChrSrcY = FFMIN(c->chrSrcH, firstChrSrcY + vChrFilterSize) - 1;
int enough_lines;
int i;
int posY, cPosY, firstPosY, lastPosY, firstCPosY, lastCPosY;
// handle holes (FAST_BILINEAR & weird filters)
if (firstLumSrcY > lastInLumBuf) {
hasLumHoles = lastInLumBuf != firstLumSrcY - 1;
if (hasLumHoles) {
hout_slice->plane[0].sliceY = firstLumSrcY;
hout_slice->plane[3].sliceY = firstLumSrcY;
hout_slice->plane[0].sliceH =
hout_slice->plane[3].sliceH = 0;
}
lastInLumBuf = firstLumSrcY - 1;
}
if (firstChrSrcY > lastInChrBuf) {
hasChrHoles = lastInChrBuf != firstChrSrcY - 1;
if (hasChrHoles) {
hout_slice->plane[1].sliceY = firstChrSrcY;
hout_slice->plane[2].sliceY = firstChrSrcY;
hout_slice->plane[1].sliceH =
hout_slice->plane[2].sliceH = 0;
}
lastInChrBuf = firstChrSrcY - 1;
}
DEBUG_BUFFERS("dstY: %d\n", dstY);
DEBUG_BUFFERS("\tfirstLumSrcY: %d lastLumSrcY: %d lastInLumBuf: %d\n",
firstLumSrcY, lastLumSrcY, lastInLumBuf);
DEBUG_BUFFERS("\tfirstChrSrcY: %d lastChrSrcY: %d lastInChrBuf: %d\n",
firstChrSrcY, lastChrSrcY, lastInChrBuf);
// Do we have enough lines in this slice to output the dstY line
enough_lines = lastLumSrcY2 < srcSliceY + srcSliceH &&
lastChrSrcY < AV_CEIL_RSHIFT(srcSliceY + srcSliceH, c->chrSrcVSubSample);
if (!enough_lines) {
lastLumSrcY = srcSliceY + srcSliceH - 1;
lastChrSrcY = chrSrcSliceY + chrSrcSliceH - 1;
DEBUG_BUFFERS("buffering slice: lastLumSrcY %d lastChrSrcY %d\n",
lastLumSrcY, lastChrSrcY);
}
av_assert0((lastLumSrcY - firstLumSrcY + 1) <= hout_slice->plane[0].available_lines);
av_assert0((lastChrSrcY - firstChrSrcY + 1) <= hout_slice->plane[1].available_lines);
posY = hout_slice->plane[0].sliceY + hout_slice->plane[0].sliceH;
if (posY <= lastLumSrcY && !hasLumHoles) {
firstPosY = FFMAX(firstLumSrcY, posY);
lastPosY = FFMIN(firstLumSrcY + hout_slice->plane[0].available_lines - 1, srcSliceY + srcSliceH - 1);
} else {
firstPosY = posY;
lastPosY = lastLumSrcY;
}
cPosY = hout_slice->plane[1].sliceY + hout_slice->plane[1].sliceH;
if (cPosY <= lastChrSrcY && !hasChrHoles) {
firstCPosY = FFMAX(firstChrSrcY, cPosY);
lastCPosY = FFMIN(firstChrSrcY + hout_slice->plane[1].available_lines - 1, AV_CEIL_RSHIFT(srcSliceY + srcSliceH, c->chrSrcVSubSample) - 1);
} else {
firstCPosY = cPosY;
lastCPosY = lastChrSrcY;
}
ff_rotate_slice(hout_slice, lastPosY, lastCPosY);
if (posY < lastLumSrcY + 1) {
for (i = lumStart; i < lumEnd; ++i)
desc[i].process(c, &desc[i], firstPosY, lastPosY - firstPosY + 1);
}
lastInLumBuf = lastLumSrcY;
if (cPosY < lastChrSrcY + 1) {
for (i = chrStart; i < chrEnd; ++i)
desc[i].process(c, &desc[i], firstCPosY, lastCPosY - firstCPosY + 1);
}
lastInChrBuf = lastChrSrcY;
if (!enough_lines)
break; // we can't output a dstY line so let's try with the next slice
#if HAVE_MMX_INLINE
ff_updateMMXDitherTables(c, dstY);
#endif
if (should_dither) {
c->chrDither8 = ff_dither_8x8_128[chrDstY & 7];
c->lumDither8 = ff_dither_8x8_128[dstY & 7];
}
if (dstY >= c->dstH - 2) {
/* hmm looks like we can't use MMX here without overwriting
* this array's tail */
ff_sws_init_output_funcs(c, &yuv2plane1, &yuv2planeX, &yuv2nv12cX,
&yuv2packed1, &yuv2packed2, &yuv2packedX, &yuv2anyX);
use_mmx_vfilter= 0;
ff_init_vscale_pfn(c, yuv2plane1, yuv2planeX, yuv2nv12cX,
yuv2packed1, yuv2packed2, yuv2packedX, yuv2anyX, use_mmx_vfilter);
}
for (i = vStart; i < vEnd; ++i)
desc[i].process(c, &desc[i], dstY, 1);
}
if (isPlanar(dstFormat) && isALPHA(dstFormat) && !needAlpha) {
int offset = lastDstY - dstSliceY;
int length = dstW;
int height = dstY - lastDstY;
if (is16BPS(dstFormat) || isNBPS(dstFormat)) {
const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(dstFormat);
fillPlane16(dst[3], dstStride[3], length, height, offset,
1, desc->comp[3].depth,
isBE(dstFormat));
} else if (is32BPS(dstFormat)) {
const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(dstFormat);
fillPlane32(dst[3], dstStride[3], length, height, offset,
1, desc->comp[3].depth,
isBE(dstFormat), desc->flags & AV_PIX_FMT_FLAG_FLOAT);
} else
fillPlane(dst[3], dstStride[3], length, height, offset, 255);
}
#if HAVE_MMXEXT_INLINE
if (av_get_cpu_flags() & AV_CPU_FLAG_MMXEXT)
__asm__ volatile ("sfence" ::: "memory");
#endif
emms_c();
/* store changed local vars back in the context */
c->dstY = dstY;
c->lastInLumBuf = lastInLumBuf;
c->lastInChrBuf = lastInChrBuf;
return dstY - lastDstY;
}
av_cold void ff_sws_init_range_convert(SwsContext *c)
{
c->lumConvertRange = NULL;
c->chrConvertRange = NULL;
if (c->srcRange != c->dstRange && !isAnyRGB(c->dstFormat)) {
if (c->dstBpc <= 14) {
if (c->srcRange) {
c->lumConvertRange = lumRangeFromJpeg_c;
c->chrConvertRange = chrRangeFromJpeg_c;
} else {
c->lumConvertRange = lumRangeToJpeg_c;
c->chrConvertRange = chrRangeToJpeg_c;
}
} else {
if (c->srcRange) {
c->lumConvertRange = lumRangeFromJpeg16_c;
c->chrConvertRange = chrRangeFromJpeg16_c;
} else {
c->lumConvertRange = lumRangeToJpeg16_c;
c->chrConvertRange = chrRangeToJpeg16_c;
}
}
}
}
static av_cold void sws_init_swscale(SwsContext *c)
{
enum AVPixelFormat srcFormat = c->srcFormat;
ff_sws_init_output_funcs(c, &c->yuv2plane1, &c->yuv2planeX,
&c->yuv2nv12cX, &c->yuv2packed1,
&c->yuv2packed2, &c->yuv2packedX, &c->yuv2anyX);
ff_sws_init_input_funcs(c);
if (c->srcBpc == 8) {
if (c->dstBpc <= 14) {
c->hyScale = c->hcScale = hScale8To15_c;
if (c->flags & SWS_FAST_BILINEAR) {
c->hyscale_fast = ff_hyscale_fast_c;
c->hcscale_fast = ff_hcscale_fast_c;
}
} else {
c->hyScale = c->hcScale = hScale8To19_c;
}
} else {
c->hyScale = c->hcScale = c->dstBpc > 14 ? hScale16To19_c
: hScale16To15_c;
}
ff_sws_init_range_convert(c);
if (!(isGray(srcFormat) || isGray(c->dstFormat) ||
srcFormat == AV_PIX_FMT_MONOBLACK || srcFormat == AV_PIX_FMT_MONOWHITE))
c->needs_hcscale = 1;
}
void ff_sws_init_scale(SwsContext *c)
{
sws_init_swscale(c);
#if ARCH_PPC
ff_sws_init_swscale_ppc(c);
#elif ARCH_X86
ff_sws_init_swscale_x86(c);
#elif ARCH_AARCH64
ff_sws_init_swscale_aarch64(c);
#elif ARCH_ARM
ff_sws_init_swscale_arm(c);
#elif ARCH_LOONGARCH64
ff_sws_init_swscale_loongarch(c);
#elif ARCH_RISCV
ff_sws_init_swscale_riscv(c);
#endif
}
static void reset_ptr(const uint8_t *src[], enum AVPixelFormat format)
{
if (!isALPHA(format))
src[3] = NULL;
if (!isPlanar(format)) {
src[3] = src[2] = NULL;
if (!usePal(format))
src[1] = NULL;
}
}
static int check_image_pointers(const uint8_t * const data[4], enum AVPixelFormat pix_fmt,
const int linesizes[4])
{
const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(pix_fmt);
int i;
av_assert2(desc);
for (i = 0; i < 4; i++) {
int plane = desc->comp[i].plane;
if (!data[plane] || !linesizes[plane])
return 0;
}
return 1;
}
static void xyz12Torgb48(struct SwsContext *c, uint16_t *dst,
const uint16_t *src, int stride, int h)
{
int xp,yp;
const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(c->srcFormat);
for (yp=0; yp<h; yp++) {
for (xp=0; xp+2<stride; xp+=3) {
int x, y, z, r, g, b;
if (desc->flags & AV_PIX_FMT_FLAG_BE) {
x = AV_RB16(src + xp + 0);
y = AV_RB16(src + xp + 1);
z = AV_RB16(src + xp + 2);
} else {
x = AV_RL16(src + xp + 0);
y = AV_RL16(src + xp + 1);
z = AV_RL16(src + xp + 2);
}
x = c->xyzgamma[x>>4];
y = c->xyzgamma[y>>4];
z = c->xyzgamma[z>>4];
// convert from XYZlinear to sRGBlinear
r = c->xyz2rgb_matrix[0][0] * x +
c->xyz2rgb_matrix[0][1] * y +
c->xyz2rgb_matrix[0][2] * z >> 12;
g = c->xyz2rgb_matrix[1][0] * x +
c->xyz2rgb_matrix[1][1] * y +
c->xyz2rgb_matrix[1][2] * z >> 12;
b = c->xyz2rgb_matrix[2][0] * x +
c->xyz2rgb_matrix[2][1] * y +
c->xyz2rgb_matrix[2][2] * z >> 12;
// limit values to 12-bit depth
r = av_clip_uintp2(r, 12);
g = av_clip_uintp2(g, 12);
b = av_clip_uintp2(b, 12);
// convert from sRGBlinear to RGB and scale from 12bit to 16bit
if (desc->flags & AV_PIX_FMT_FLAG_BE) {
AV_WB16(dst + xp + 0, c->rgbgamma[r] << 4);
AV_WB16(dst + xp + 1, c->rgbgamma[g] << 4);
AV_WB16(dst + xp + 2, c->rgbgamma[b] << 4);
} else {
AV_WL16(dst + xp + 0, c->rgbgamma[r] << 4);
AV_WL16(dst + xp + 1, c->rgbgamma[g] << 4);
AV_WL16(dst + xp + 2, c->rgbgamma[b] << 4);
}
}
src += stride;
dst += stride;
}
}
static void rgb48Toxyz12(struct SwsContext *c, uint16_t *dst,
const uint16_t *src, int stride, int h)
{
int xp,yp;
const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(c->dstFormat);
for (yp=0; yp<h; yp++) {
for (xp=0; xp+2<stride; xp+=3) {
int x, y, z, r, g, b;
if (desc->flags & AV_PIX_FMT_FLAG_BE) {
r = AV_RB16(src + xp + 0);
g = AV_RB16(src + xp + 1);
b = AV_RB16(src + xp + 2);
} else {
r = AV_RL16(src + xp + 0);
g = AV_RL16(src + xp + 1);
b = AV_RL16(src + xp + 2);
}
r = c->rgbgammainv[r>>4];
g = c->rgbgammainv[g>>4];
b = c->rgbgammainv[b>>4];
// convert from sRGBlinear to XYZlinear
x = c->rgb2xyz_matrix[0][0] * r +
c->rgb2xyz_matrix[0][1] * g +
c->rgb2xyz_matrix[0][2] * b >> 12;
y = c->rgb2xyz_matrix[1][0] * r +
c->rgb2xyz_matrix[1][1] * g +
c->rgb2xyz_matrix[1][2] * b >> 12;
z = c->rgb2xyz_matrix[2][0] * r +
c->rgb2xyz_matrix[2][1] * g +
c->rgb2xyz_matrix[2][2] * b >> 12;
// limit values to 12-bit depth
x = av_clip_uintp2(x, 12);
y = av_clip_uintp2(y, 12);
z = av_clip_uintp2(z, 12);
// convert from XYZlinear to X'Y'Z' and scale from 12bit to 16bit
if (desc->flags & AV_PIX_FMT_FLAG_BE) {
AV_WB16(dst + xp + 0, c->xyzgammainv[x] << 4);
AV_WB16(dst + xp + 1, c->xyzgammainv[y] << 4);
AV_WB16(dst + xp + 2, c->xyzgammainv[z] << 4);
} else {
AV_WL16(dst + xp + 0, c->xyzgammainv[x] << 4);
AV_WL16(dst + xp + 1, c->xyzgammainv[y] << 4);
AV_WL16(dst + xp + 2, c->xyzgammainv[z] << 4);
}
}
src += stride;
dst += stride;
}
}
static void update_palette(SwsContext *c, const uint32_t *pal)
{
for (int i = 0; i < 256; i++) {
int r, g, b, y, u, v, a = 0xff;
if (c->srcFormat == AV_PIX_FMT_PAL8) {
uint32_t p = pal[i];
a = (p >> 24) & 0xFF;
r = (p >> 16) & 0xFF;
g = (p >> 8) & 0xFF;
b = p & 0xFF;
} else if (c->srcFormat == AV_PIX_FMT_RGB8) {
r = ( i >> 5 ) * 36;
g = ((i >> 2) & 7) * 36;
b = ( i & 3) * 85;
} else if (c->srcFormat == AV_PIX_FMT_BGR8) {
b = ( i >> 6 ) * 85;
g = ((i >> 3) & 7) * 36;
r = ( i & 7) * 36;
} else if (c->srcFormat == AV_PIX_FMT_RGB4_BYTE) {
r = ( i >> 3 ) * 255;
g = ((i >> 1) & 3) * 85;
b = ( i & 1) * 255;
} else if (c->srcFormat == AV_PIX_FMT_GRAY8 || c->srcFormat == AV_PIX_FMT_GRAY8A) {
r = g = b = i;
} else {
av_assert1(c->srcFormat == AV_PIX_FMT_BGR4_BYTE);
b = ( i >> 3 ) * 255;
g = ((i >> 1) & 3) * 85;
r = ( i & 1) * 255;
}
#define RGB2YUV_SHIFT 15
#define BY ( (int) (0.114 * 219 / 255 * (1 << RGB2YUV_SHIFT) + 0.5))
#define BV (-(int) (0.081 * 224 / 255 * (1 << RGB2YUV_SHIFT) + 0.5))
#define BU ( (int) (0.500 * 224 / 255 * (1 << RGB2YUV_SHIFT) + 0.5))
#define GY ( (int) (0.587 * 219 / 255 * (1 << RGB2YUV_SHIFT) + 0.5))
#define GV (-(int) (0.419 * 224 / 255 * (1 << RGB2YUV_SHIFT) + 0.5))
#define GU (-(int) (0.331 * 224 / 255 * (1 << RGB2YUV_SHIFT) + 0.5))
#define RY ( (int) (0.299 * 219 / 255 * (1 << RGB2YUV_SHIFT) + 0.5))
#define RV ( (int) (0.500 * 224 / 255 * (1 << RGB2YUV_SHIFT) + 0.5))
#define RU (-(int) (0.169 * 224 / 255 * (1 << RGB2YUV_SHIFT) + 0.5))
y = av_clip_uint8((RY * r + GY * g + BY * b + ( 33 << (RGB2YUV_SHIFT - 1))) >> RGB2YUV_SHIFT);
u = av_clip_uint8((RU * r + GU * g + BU * b + (257 << (RGB2YUV_SHIFT - 1))) >> RGB2YUV_SHIFT);
v = av_clip_uint8((RV * r + GV * g + BV * b + (257 << (RGB2YUV_SHIFT - 1))) >> RGB2YUV_SHIFT);
c->pal_yuv[i]= y + (u<<8) + (v<<16) + ((unsigned)a<<24);
switch (c->dstFormat) {
case AV_PIX_FMT_BGR32:
#if !HAVE_BIGENDIAN
case AV_PIX_FMT_RGB24:
#endif
c->pal_rgb[i]= r + (g<<8) + (b<<16) + ((unsigned)a<<24);
break;
case AV_PIX_FMT_BGR32_1:
#if HAVE_BIGENDIAN
case AV_PIX_FMT_BGR24:
#endif
c->pal_rgb[i]= a + (r<<8) + (g<<16) + ((unsigned)b<<24);
break;
case AV_PIX_FMT_RGB32_1:
#if HAVE_BIGENDIAN
case AV_PIX_FMT_RGB24:
#endif
c->pal_rgb[i]= a + (b<<8) + (g<<16) + ((unsigned)r<<24);
break;
case AV_PIX_FMT_RGB32:
#if !HAVE_BIGENDIAN
case AV_PIX_FMT_BGR24:
#endif
default:
c->pal_rgb[i]= b + (g<<8) + (r<<16) + ((unsigned)a<<24);
}
}
}
static int scale_internal(SwsContext *c,
const uint8_t * const srcSlice[], const int srcStride[],
int srcSliceY, int srcSliceH,
uint8_t *const dstSlice[], const int dstStride[],
int dstSliceY, int dstSliceH);
static int scale_gamma(SwsContext *c,
const uint8_t * const srcSlice[], const int srcStride[],
int srcSliceY, int srcSliceH,
uint8_t * const dstSlice[], const int dstStride[],
int dstSliceY, int dstSliceH)
{
int ret = scale_internal(c->cascaded_context[0],
srcSlice, srcStride, srcSliceY, srcSliceH,
c->cascaded_tmp, c->cascaded_tmpStride, 0, c->srcH);
if (ret < 0)
return ret;
if (c->cascaded_context[2])
ret = scale_internal(c->cascaded_context[1], (const uint8_t * const *)c->cascaded_tmp,
c->cascaded_tmpStride, srcSliceY, srcSliceH,
c->cascaded1_tmp, c->cascaded1_tmpStride, 0, c->dstH);
else
ret = scale_internal(c->cascaded_context[1], (const uint8_t * const *)c->cascaded_tmp,
c->cascaded_tmpStride, srcSliceY, srcSliceH,
dstSlice, dstStride, dstSliceY, dstSliceH);
if (ret < 0)
return ret;
if (c->cascaded_context[2]) {
ret = scale_internal(c->cascaded_context[2], (const uint8_t * const *)c->cascaded1_tmp,
c->cascaded1_tmpStride, c->cascaded_context[1]->dstY - ret,
c->cascaded_context[1]->dstY,
dstSlice, dstStride, dstSliceY, dstSliceH);
}
return ret;
}
static int scale_cascaded(SwsContext *c,
const uint8_t * const srcSlice[], const int srcStride[],
int srcSliceY, int srcSliceH,
uint8_t * const dstSlice[], const int dstStride[],
int dstSliceY, int dstSliceH)
{
int ret = scale_internal(c->cascaded_context[0],
srcSlice, srcStride, srcSliceY, srcSliceH,
c->cascaded_tmp, c->cascaded_tmpStride,
0, c->cascaded_context[0]->dstH);
if (ret < 0)
return ret;
ret = scale_internal(c->cascaded_context[1],
(const uint8_t * const * )c->cascaded_tmp, c->cascaded_tmpStride,
0, c->cascaded_context[0]->dstH,
dstSlice, dstStride, dstSliceY, dstSliceH);
return ret;
}
static int scale_internal(SwsContext *c,
const uint8_t * const srcSlice[], const int srcStride[],
int srcSliceY, int srcSliceH,
uint8_t *const dstSlice[], const int dstStride[],
int dstSliceY, int dstSliceH)
{
const int scale_dst = dstSliceY > 0 || dstSliceH < c->dstH;
const int frame_start = scale_dst || !c->sliceDir;
int i, ret;
const uint8_t *src2[4];
uint8_t *dst2[4];
int macro_height_src = isBayer(c->srcFormat) ? 2 : (1 << c->chrSrcVSubSample);
int macro_height_dst = isBayer(c->dstFormat) ? 2 : (1 << c->chrDstVSubSample);
// copy strides, so they can safely be modified
int srcStride2[4];
int dstStride2[4];
int srcSliceY_internal = srcSliceY;
if (!srcStride || !dstStride || !dstSlice || !srcSlice) {
av_log(c, AV_LOG_ERROR, "One of the input parameters to sws_scale() is NULL, please check the calling code\n");
return AVERROR(EINVAL);
}
if ((srcSliceY & (macro_height_src - 1)) ||
((srcSliceH & (macro_height_src - 1)) && srcSliceY + srcSliceH != c->srcH) ||
srcSliceY + srcSliceH > c->srcH ||
(isBayer(c->srcFormat) && srcSliceH <= 1)) {
av_log(c, AV_LOG_ERROR, "Slice parameters %d, %d are invalid\n", srcSliceY, srcSliceH);
return AVERROR(EINVAL);
}
if ((dstSliceY & (macro_height_dst - 1)) ||
((dstSliceH & (macro_height_dst - 1)) && dstSliceY + dstSliceH != c->dstH) ||
dstSliceY + dstSliceH > c->dstH) {
av_log(c, AV_LOG_ERROR, "Slice parameters %d, %d are invalid\n", dstSliceY, dstSliceH);
return AVERROR(EINVAL);
}
if (!check_image_pointers(srcSlice, c->srcFormat, srcStride)) {
av_log(c, AV_LOG_ERROR, "bad src image pointers\n");
return AVERROR(EINVAL);
}
if (!check_image_pointers((const uint8_t* const*)dstSlice, c->dstFormat, dstStride)) {
av_log(c, AV_LOG_ERROR, "bad dst image pointers\n");
return AVERROR(EINVAL);
}
// do not mess up sliceDir if we have a "trailing" 0-size slice
if (srcSliceH == 0)
return 0;
if (c->gamma_flag && c->cascaded_context[0])
return scale_gamma(c, srcSlice, srcStride, srcSliceY, srcSliceH,
dstSlice, dstStride, dstSliceY, dstSliceH);
if (c->cascaded_context[0] && srcSliceY == 0 && srcSliceH == c->cascaded_context[0]->srcH)
return scale_cascaded(c, srcSlice, srcStride, srcSliceY, srcSliceH,
dstSlice, dstStride, dstSliceY, dstSliceH);
if (!srcSliceY && (c->flags & SWS_BITEXACT) && c->dither == SWS_DITHER_ED && c->dither_error[0])
for (i = 0; i < 4; i++)
memset(c->dither_error[i], 0, sizeof(c->dither_error[0][0]) * (c->dstW+2));
if (usePal(c->srcFormat))
update_palette(c, (const uint32_t *)srcSlice[1]);
memcpy(src2, srcSlice, sizeof(src2));
memcpy(dst2, dstSlice, sizeof(dst2));
memcpy(srcStride2, srcStride, sizeof(srcStride2));
memcpy(dstStride2, dstStride, sizeof(dstStride2));
if (frame_start && !scale_dst) {
if (srcSliceY != 0 && srcSliceY + srcSliceH != c->srcH) {
av_log(c, AV_LOG_ERROR, "Slices start in the middle!\n");
return AVERROR(EINVAL);
}
c->sliceDir = (srcSliceY == 0) ? 1 : -1;
} else if (scale_dst)
c->sliceDir = 1;
if (c->src0Alpha && !c->dst0Alpha && isALPHA(c->dstFormat)) {
uint8_t *base;
int x,y;
av_fast_malloc(&c->rgb0_scratch, &c->rgb0_scratch_allocated,
FFABS(srcStride[0]) * srcSliceH + 32);
if (!c->rgb0_scratch)
return AVERROR(ENOMEM);
base = srcStride[0] < 0 ? c->rgb0_scratch - srcStride[0] * (srcSliceH-1) :
c->rgb0_scratch;
for (y=0; y<srcSliceH; y++){
memcpy(base + srcStride[0]*y, src2[0] + srcStride[0]*y, 4*c->srcW);
for (x=c->src0Alpha-1; x<4*c->srcW; x+=4) {
base[ srcStride[0]*y + x] = 0xFF;
}
}
src2[0] = base;
}
if (c->srcXYZ && !(c->dstXYZ && c->srcW==c->dstW && c->srcH==c->dstH)) {
uint8_t *base;
av_fast_malloc(&c->xyz_scratch, &c->xyz_scratch_allocated,
FFABS(srcStride[0]) * srcSliceH + 32);
if (!c->xyz_scratch)
return AVERROR(ENOMEM);
base = srcStride[0] < 0 ? c->xyz_scratch - srcStride[0] * (srcSliceH-1) :
c->xyz_scratch;
xyz12Torgb48(c, (uint16_t*)base, (const uint16_t*)src2[0], srcStride[0]/2, srcSliceH);
src2[0] = base;
}
if (c->sliceDir != 1) {
// slices go from bottom to top => we flip the image internally
for (i=0; i<4; i++) {
srcStride2[i] *= -1;
dstStride2[i] *= -1;
}
src2[0] += (srcSliceH - 1) * srcStride[0];
if (!usePal(c->srcFormat))
src2[1] += ((srcSliceH >> c->chrSrcVSubSample) - 1) * srcStride[1];
src2[2] += ((srcSliceH >> c->chrSrcVSubSample) - 1) * srcStride[2];
src2[3] += (srcSliceH - 1) * srcStride[3];
dst2[0] += ( c->dstH - 1) * dstStride[0];
dst2[1] += ((c->dstH >> c->chrDstVSubSample) - 1) * dstStride[1];
dst2[2] += ((c->dstH >> c->chrDstVSubSample) - 1) * dstStride[2];
dst2[3] += ( c->dstH - 1) * dstStride[3];
srcSliceY_internal = c->srcH-srcSliceY-srcSliceH;
}
reset_ptr(src2, c->srcFormat);
reset_ptr((void*)dst2, c->dstFormat);
if (c->convert_unscaled) {
int offset = srcSliceY_internal;
int slice_h = srcSliceH;
// for dst slice scaling, offset the pointers to match the unscaled API
if (scale_dst) {
av_assert0(offset == 0);
for (i = 0; i < 4 && src2[i]; i++) {
if (!src2[i] || (i > 0 && usePal(c->srcFormat)))
break;
src2[i] += (dstSliceY >> ((i == 1 || i == 2) ? c->chrSrcVSubSample : 0)) * srcStride2[i];
}
for (i = 0; i < 4 && dst2[i]; i++) {
if (!dst2[i] || (i > 0 && usePal(c->dstFormat)))
break;
dst2[i] -= (dstSliceY >> ((i == 1 || i == 2) ? c->chrDstVSubSample : 0)) * dstStride2[i];
}
offset = dstSliceY;
slice_h = dstSliceH;
}
ret = c->convert_unscaled(c, src2, srcStride2, offset, slice_h,
dst2, dstStride2);
if (scale_dst)
dst2[0] += dstSliceY * dstStride2[0];
} else {
ret = swscale(c, src2, srcStride2, srcSliceY_internal, srcSliceH,
dst2, dstStride2, dstSliceY, dstSliceH);
}
if (c->dstXYZ && !(c->srcXYZ && c->srcW==c->dstW && c->srcH==c->dstH)) {
uint16_t *dst16;
if (scale_dst) {
dst16 = (uint16_t *)dst2[0];
} else {
int dstY = c->dstY ? c->dstY : srcSliceY + srcSliceH;
av_assert0(dstY >= ret);
av_assert0(ret >= 0);
av_assert0(c->dstH >= dstY);
dst16 = (uint16_t*)(dst2[0] + (dstY - ret) * dstStride2[0]);
}
/* replace on the same data */
rgb48Toxyz12(c, dst16, dst16, dstStride2[0]/2, ret);
}
/* reset slice direction at end of frame */
if ((srcSliceY_internal + srcSliceH == c->srcH) || scale_dst)
c->sliceDir = 0;
return ret;
}
void sws_frame_end(struct SwsContext *c)
{
av_frame_unref(c->frame_src);
av_frame_unref(c->frame_dst);
c->src_ranges.nb_ranges = 0;
}
int sws_frame_start(struct SwsContext *c, AVFrame *dst, const AVFrame *src)
{
int ret, allocated = 0;
ret = av_frame_ref(c->frame_src, src);
if (ret < 0)
return ret;
if (!dst->buf[0]) {
dst->width = c->dstW;
dst->height = c->dstH;
dst->format = c->dstFormat;
ret = av_frame_get_buffer(dst, 0);
if (ret < 0)
return ret;
allocated = 1;
}
ret = av_frame_ref(c->frame_dst, dst);
if (ret < 0) {
if (allocated)
av_frame_unref(dst);
return ret;
}
return 0;
}
int sws_send_slice(struct SwsContext *c, unsigned int slice_start,
unsigned int slice_height)
{
int ret;
ret = ff_range_add(&c->src_ranges, slice_start, slice_height);
if (ret < 0)
return ret;
return 0;
}
unsigned int sws_receive_slice_alignment(const struct SwsContext *c)
{
if (c->slice_ctx)
return c->slice_ctx[0]->dst_slice_align;
return c->dst_slice_align;
}
int sws_receive_slice(struct SwsContext *c, unsigned int slice_start,
unsigned int slice_height)
{
unsigned int align = sws_receive_slice_alignment(c);
uint8_t *dst[4];
/* wait until complete input has been received */
if (!(c->src_ranges.nb_ranges == 1 &&
c->src_ranges.ranges[0].start == 0 &&
c->src_ranges.ranges[0].len == c->srcH))
return AVERROR(EAGAIN);
if ((slice_start > 0 || slice_height < c->dstH) &&
(slice_start % align || slice_height % align)) {
av_log(c, AV_LOG_ERROR,
"Incorrectly aligned output: %u/%u not multiples of %u\n",
slice_start, slice_height, align);
return AVERROR(EINVAL);
}
if (c->slicethread) {
int nb_jobs = c->slice_ctx[0]->dither == SWS_DITHER_ED ? 1 : c->nb_slice_ctx;
int ret = 0;
c->dst_slice_start = slice_start;
c->dst_slice_height = slice_height;
avpriv_slicethread_execute(c->slicethread, nb_jobs, 0);
for (int i = 0; i < c->nb_slice_ctx; i++) {
if (c->slice_err[i] < 0) {
ret = c->slice_err[i];
break;
}
}
memset(c->slice_err, 0, c->nb_slice_ctx * sizeof(*c->slice_err));
return ret;
}
for (int i = 0; i < FF_ARRAY_ELEMS(dst); i++) {
ptrdiff_t offset = c->frame_dst->linesize[i] * (ptrdiff_t)(slice_start >> c->chrDstVSubSample);
dst[i] = FF_PTR_ADD(c->frame_dst->data[i], offset);
}
return scale_internal(c, (const uint8_t * const *)c->frame_src->data,
c->frame_src->linesize, 0, c->srcH,
dst, c->frame_dst->linesize, slice_start, slice_height);
}
int sws_scale_frame(struct SwsContext *c, AVFrame *dst, const AVFrame *src)
{
int ret;
ret = sws_frame_start(c, dst, src);
if (ret < 0)
return ret;
ret = sws_send_slice(c, 0, src->height);
if (ret >= 0)
ret = sws_receive_slice(c, 0, dst->height);
sws_frame_end(c);
return ret;
}
/**
* swscale wrapper, so we don't need to export the SwsContext.
* Assumes planar YUV to be in YUV order instead of YVU.
*/
int attribute_align_arg sws_scale(struct SwsContext *c,
const uint8_t * const srcSlice[],
const int srcStride[], int srcSliceY,
int srcSliceH, uint8_t *const dst[],
const int dstStride[])
{
if (c->nb_slice_ctx)
c = c->slice_ctx[0];
return scale_internal(c, srcSlice, srcStride, srcSliceY, srcSliceH,
dst, dstStride, 0, c->dstH);
}
void ff_sws_slice_worker(void *priv, int jobnr, int threadnr,
int nb_jobs, int nb_threads)
{
SwsContext *parent = priv;
SwsContext *c = parent->slice_ctx[threadnr];
const int slice_height = FFALIGN(FFMAX((parent->dst_slice_height + nb_jobs - 1) / nb_jobs, 1),
c->dst_slice_align);
const int slice_start = jobnr * slice_height;
const int slice_end = FFMIN((jobnr + 1) * slice_height, parent->dst_slice_height);
int err = 0;
if (slice_end > slice_start) {
uint8_t *dst[4] = { NULL };
for (int i = 0; i < FF_ARRAY_ELEMS(dst) && parent->frame_dst->data[i]; i++) {
const int vshift = (i == 1 || i == 2) ? c->chrDstVSubSample : 0;
const ptrdiff_t offset = parent->frame_dst->linesize[i] *
(ptrdiff_t)((slice_start + parent->dst_slice_start) >> vshift);
dst[i] = parent->frame_dst->data[i] + offset;
}
err = scale_internal(c, (const uint8_t * const *)parent->frame_src->data,
parent->frame_src->linesize, 0, c->srcH,
dst, parent->frame_dst->linesize,
parent->dst_slice_start + slice_start, slice_end - slice_start);
}
parent->slice_err[threadnr] = err;
}