ffmpeg/libswscale/vscale.c
Andreas Rheinhardt 2fae000994 swscale/vscale: Increase type strictness
libswscale/vscale.c makes extensive use of function pointers and in
doing so it converts these function pointers to and from a pointer to
void. Yet this is actually against the C standard:
C90 only guarantees that one can convert a pointer to any incomplete
type or object type to void* and back with the result comparing equal
to the original which makes pointers to void generic pointers to
incomplete or object type. Yet C90 lacks a generic function pointer
type.
C99 additionally guarantees that a pointer to a function of one type may
be converted to a pointer to a function of another type with the result
and the original comparing equal when converting back.
This makes any function pointer type a generic function pointer type.
Yet even this does not make pointers to void generic function pointers.

Both GCC and Clang emit warnings for this when in pedantic mode.

This commit fixes this by using a union that can hold one member of any
of the required function pointer types to store the function pointer.
This works even for C90.

Reviewed-by: Michael Niedermayer <michael@niedermayer.cc>
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
2020-04-27 23:34:31 +02:00

323 lines
13 KiB
C

/*
* Copyright (C) 2015 Pedro Arthur <bygrandao@gmail.com>
*
* 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 "swscale_internal.h"
typedef struct VScalerContext
{
uint16_t *filter[2];
int32_t *filter_pos;
int filter_size;
int isMMX;
union {
yuv2planar1_fn yuv2planar1;
yuv2planarX_fn yuv2planarX;
yuv2interleavedX_fn yuv2interleavedX;
yuv2packed1_fn yuv2packed1;
yuv2packed2_fn yuv2packed2;
yuv2anyX_fn yuv2anyX;
} pfn;
yuv2packedX_fn yuv2packedX;
} VScalerContext;
static int lum_planar_vscale(SwsContext *c, SwsFilterDescriptor *desc, int sliceY, int sliceH)
{
VScalerContext *inst = desc->instance;
int dstW = desc->dst->width;
int first = FFMAX(1-inst->filter_size, inst->filter_pos[sliceY]);
int sp = first - desc->src->plane[0].sliceY;
int dp = sliceY - desc->dst->plane[0].sliceY;
uint8_t **src = desc->src->plane[0].line + sp;
uint8_t **dst = desc->dst->plane[0].line + dp;
uint16_t *filter = inst->filter[0] + (inst->isMMX ? 0 : sliceY * inst->filter_size);
if (inst->filter_size == 1)
inst->pfn.yuv2planar1((const int16_t*)src[0], dst[0], dstW, c->lumDither8, 0);
else
inst->pfn.yuv2planarX(filter, inst->filter_size, (const int16_t**)src, dst[0], dstW, c->lumDither8, 0);
if (desc->alpha) {
int sp = first - desc->src->plane[3].sliceY;
int dp = sliceY - desc->dst->plane[3].sliceY;
uint8_t **src = desc->src->plane[3].line + sp;
uint8_t **dst = desc->dst->plane[3].line + dp;
uint16_t *filter = inst->filter[1] + (inst->isMMX ? 0 : sliceY * inst->filter_size);
if (inst->filter_size == 1)
inst->pfn.yuv2planar1((const int16_t*)src[0], dst[0], dstW, c->lumDither8, 0);
else
inst->pfn.yuv2planarX(filter, inst->filter_size, (const int16_t**)src, dst[0], dstW, c->lumDither8, 0);
}
return 1;
}
static int chr_planar_vscale(SwsContext *c, SwsFilterDescriptor *desc, int sliceY, int sliceH)
{
const int chrSkipMask = (1 << desc->dst->v_chr_sub_sample) - 1;
if (sliceY & chrSkipMask)
return 0;
else {
VScalerContext *inst = desc->instance;
int dstW = AV_CEIL_RSHIFT(desc->dst->width, desc->dst->h_chr_sub_sample);
int chrSliceY = sliceY >> desc->dst->v_chr_sub_sample;
int first = FFMAX(1-inst->filter_size, inst->filter_pos[chrSliceY]);
int sp1 = first - desc->src->plane[1].sliceY;
int sp2 = first - desc->src->plane[2].sliceY;
int dp1 = chrSliceY - desc->dst->plane[1].sliceY;
int dp2 = chrSliceY - desc->dst->plane[2].sliceY;
uint8_t **src1 = desc->src->plane[1].line + sp1;
uint8_t **src2 = desc->src->plane[2].line + sp2;
uint8_t **dst1 = desc->dst->plane[1].line + dp1;
uint8_t **dst2 = desc->dst->plane[2].line + dp2;
uint16_t *filter = inst->filter[0] + (inst->isMMX ? 0 : chrSliceY * inst->filter_size);
if (c->yuv2nv12cX) {
inst->pfn.yuv2interleavedX(c, filter, inst->filter_size, (const int16_t**)src1, (const int16_t**)src2, dst1[0], dstW);
} else if (inst->filter_size == 1) {
inst->pfn.yuv2planar1((const int16_t*)src1[0], dst1[0], dstW, c->chrDither8, 0);
inst->pfn.yuv2planar1((const int16_t*)src2[0], dst2[0], dstW, c->chrDither8, 3);
} else {
inst->pfn.yuv2planarX(filter, inst->filter_size, (const int16_t**)src1, dst1[0], dstW, c->chrDither8, 0);
inst->pfn.yuv2planarX(filter, inst->filter_size, (const int16_t**)src2, dst2[0], dstW, c->chrDither8, inst->isMMX ? (c->uv_offx2 >> 1) : 3);
}
}
return 1;
}
static int packed_vscale(SwsContext *c, SwsFilterDescriptor *desc, int sliceY, int sliceH)
{
VScalerContext *inst = desc->instance;
int dstW = desc->dst->width;
int chrSliceY = sliceY >> desc->dst->v_chr_sub_sample;
int lum_fsize = inst[0].filter_size;
int chr_fsize = inst[1].filter_size;
uint16_t *lum_filter = inst[0].filter[0];
uint16_t *chr_filter = inst[1].filter[0];
int firstLum = FFMAX(1-lum_fsize, inst[0].filter_pos[ sliceY]);
int firstChr = FFMAX(1-chr_fsize, inst[1].filter_pos[chrSliceY]);
int sp0 = firstLum - desc->src->plane[0].sliceY;
int sp1 = firstChr - desc->src->plane[1].sliceY;
int sp2 = firstChr - desc->src->plane[2].sliceY;
int sp3 = firstLum - desc->src->plane[3].sliceY;
int dp = sliceY - desc->dst->plane[0].sliceY;
uint8_t **src0 = desc->src->plane[0].line + sp0;
uint8_t **src1 = desc->src->plane[1].line + sp1;
uint8_t **src2 = desc->src->plane[2].line + sp2;
uint8_t **src3 = desc->alpha ? desc->src->plane[3].line + sp3 : NULL;
uint8_t **dst = desc->dst->plane[0].line + dp;
if (c->yuv2packed1 && lum_fsize == 1 && chr_fsize == 1) { // unscaled RGB
inst->pfn.yuv2packed1(c, (const int16_t*)*src0, (const int16_t**)src1, (const int16_t**)src2,
(const int16_t*)(desc->alpha ? *src3 : NULL), *dst, dstW, 0, sliceY);
} else if (c->yuv2packed1 && lum_fsize == 1 && chr_fsize == 2 &&
chr_filter[2 * chrSliceY + 1] + chr_filter[2 * chrSliceY] == 4096 &&
chr_filter[2 * chrSliceY + 1] <= 4096U) { // unscaled RGB
int chrAlpha = chr_filter[2 * chrSliceY + 1];
inst->pfn.yuv2packed1(c, (const int16_t*)*src0, (const int16_t**)src1, (const int16_t**)src2,
(const int16_t*)(desc->alpha ? *src3 : NULL), *dst, dstW, chrAlpha, sliceY);
} else if (c->yuv2packed2 && lum_fsize == 2 && chr_fsize == 2 &&
lum_filter[2 * sliceY + 1] + lum_filter[2 * sliceY] == 4096 &&
lum_filter[2 * sliceY + 1] <= 4096U &&
chr_filter[2 * chrSliceY + 1] + chr_filter[2 * chrSliceY] == 4096 &&
chr_filter[2 * chrSliceY + 1] <= 4096U
) { // bilinear upscale RGB
int lumAlpha = lum_filter[2 * sliceY + 1];
int chrAlpha = chr_filter[2 * chrSliceY + 1];
c->lumMmxFilter[2] =
c->lumMmxFilter[3] = lum_filter[2 * sliceY] * 0x10001;
c->chrMmxFilter[2] =
c->chrMmxFilter[3] = chr_filter[2 * chrSliceY] * 0x10001;
inst->pfn.yuv2packed2(c, (const int16_t**)src0, (const int16_t**)src1, (const int16_t**)src2, (const int16_t**)src3,
*dst, dstW, lumAlpha, chrAlpha, sliceY);
} else { // general RGB
if ((c->yuv2packed1 && lum_fsize == 1 && chr_fsize == 2) ||
(c->yuv2packed2 && lum_fsize == 2 && chr_fsize == 2)) {
if (!c->warned_unuseable_bilinear)
av_log(c, AV_LOG_INFO, "Optimized 2 tap filter code cannot be used\n");
c->warned_unuseable_bilinear = 1;
}
inst->yuv2packedX(c, lum_filter + sliceY * lum_fsize,
(const int16_t**)src0, lum_fsize, chr_filter + chrSliceY * chr_fsize,
(const int16_t**)src1, (const int16_t**)src2, chr_fsize, (const int16_t**)src3, *dst, dstW, sliceY);
}
return 1;
}
static int any_vscale(SwsContext *c, SwsFilterDescriptor *desc, int sliceY, int sliceH)
{
VScalerContext *inst = desc->instance;
int dstW = desc->dst->width;
int chrSliceY = sliceY >> desc->dst->v_chr_sub_sample;
int lum_fsize = inst[0].filter_size;
int chr_fsize = inst[1].filter_size;
uint16_t *lum_filter = inst[0].filter[0];
uint16_t *chr_filter = inst[1].filter[0];
int firstLum = FFMAX(1-lum_fsize, inst[0].filter_pos[ sliceY]);
int firstChr = FFMAX(1-chr_fsize, inst[1].filter_pos[chrSliceY]);
int sp0 = firstLum - desc->src->plane[0].sliceY;
int sp1 = firstChr - desc->src->plane[1].sliceY;
int sp2 = firstChr - desc->src->plane[2].sliceY;
int sp3 = firstLum - desc->src->plane[3].sliceY;
int dp0 = sliceY - desc->dst->plane[0].sliceY;
int dp1 = chrSliceY - desc->dst->plane[1].sliceY;
int dp2 = chrSliceY - desc->dst->plane[2].sliceY;
int dp3 = sliceY - desc->dst->plane[3].sliceY;
uint8_t **src0 = desc->src->plane[0].line + sp0;
uint8_t **src1 = desc->src->plane[1].line + sp1;
uint8_t **src2 = desc->src->plane[2].line + sp2;
uint8_t **src3 = desc->alpha ? desc->src->plane[3].line + sp3 : NULL;
uint8_t *dst[4] = { desc->dst->plane[0].line[dp0],
desc->dst->plane[1].line[dp1],
desc->dst->plane[2].line[dp2],
desc->alpha ? desc->dst->plane[3].line[dp3] : NULL };
av_assert1(!c->yuv2packed1 && !c->yuv2packed2);
inst->pfn.yuv2anyX(c, lum_filter + sliceY * lum_fsize,
(const int16_t**)src0, lum_fsize, chr_filter + sliceY * chr_fsize,
(const int16_t**)src1, (const int16_t**)src2, chr_fsize, (const int16_t**)src3, dst, dstW, sliceY);
return 1;
}
int ff_init_vscale(SwsContext *c, SwsFilterDescriptor *desc, SwsSlice *src, SwsSlice *dst)
{
VScalerContext *lumCtx = NULL;
VScalerContext *chrCtx = NULL;
if (isPlanarYUV(c->dstFormat) || (isGray(c->dstFormat) && !isALPHA(c->dstFormat))) {
lumCtx = av_mallocz(sizeof(VScalerContext));
if (!lumCtx)
return AVERROR(ENOMEM);
desc[0].process = lum_planar_vscale;
desc[0].instance = lumCtx;
desc[0].src = src;
desc[0].dst = dst;
desc[0].alpha = c->needAlpha;
if (!isGray(c->dstFormat)) {
chrCtx = av_mallocz(sizeof(VScalerContext));
if (!chrCtx)
return AVERROR(ENOMEM);
desc[1].process = chr_planar_vscale;
desc[1].instance = chrCtx;
desc[1].src = src;
desc[1].dst = dst;
}
} else {
lumCtx = av_mallocz_array(sizeof(VScalerContext), 2);
if (!lumCtx)
return AVERROR(ENOMEM);
chrCtx = &lumCtx[1];
desc[0].process = c->yuv2packedX ? packed_vscale : any_vscale;
desc[0].instance = lumCtx;
desc[0].src = src;
desc[0].dst = dst;
desc[0].alpha = c->needAlpha;
}
ff_init_vscale_pfn(c, c->yuv2plane1, c->yuv2planeX, c->yuv2nv12cX,
c->yuv2packed1, c->yuv2packed2, c->yuv2packedX, c->yuv2anyX, c->use_mmx_vfilter);
return 0;
}
void ff_init_vscale_pfn(SwsContext *c,
yuv2planar1_fn yuv2plane1,
yuv2planarX_fn yuv2planeX,
yuv2interleavedX_fn yuv2nv12cX,
yuv2packed1_fn yuv2packed1,
yuv2packed2_fn yuv2packed2,
yuv2packedX_fn yuv2packedX,
yuv2anyX_fn yuv2anyX, int use_mmx)
{
VScalerContext *lumCtx = NULL;
VScalerContext *chrCtx = NULL;
int idx = c->numDesc - (c->is_internal_gamma ? 2 : 1); //FIXME avoid hardcoding indexes
if (isPlanarYUV(c->dstFormat) || (isGray(c->dstFormat) && !isALPHA(c->dstFormat))) {
if (!isGray(c->dstFormat)) {
chrCtx = c->desc[idx].instance;
chrCtx->filter[0] = use_mmx ? (int16_t*)c->chrMmxFilter : c->vChrFilter;
chrCtx->filter_size = c->vChrFilterSize;
chrCtx->filter_pos = c->vChrFilterPos;
chrCtx->isMMX = use_mmx;
--idx;
if (yuv2nv12cX) chrCtx->pfn.yuv2interleavedX = yuv2nv12cX;
else if (c->vChrFilterSize == 1) chrCtx->pfn.yuv2planar1 = yuv2plane1;
else chrCtx->pfn.yuv2planarX = yuv2planeX;
}
lumCtx = c->desc[idx].instance;
lumCtx->filter[0] = use_mmx ? (int16_t*)c->lumMmxFilter : c->vLumFilter;
lumCtx->filter[1] = use_mmx ? (int16_t*)c->alpMmxFilter : c->vLumFilter;
lumCtx->filter_size = c->vLumFilterSize;
lumCtx->filter_pos = c->vLumFilterPos;
lumCtx->isMMX = use_mmx;
if (c->vLumFilterSize == 1) lumCtx->pfn.yuv2planar1 = yuv2plane1;
else lumCtx->pfn.yuv2planarX = yuv2planeX;
} else {
lumCtx = c->desc[idx].instance;
chrCtx = &lumCtx[1];
lumCtx->filter[0] = c->vLumFilter;
lumCtx->filter_size = c->vLumFilterSize;
lumCtx->filter_pos = c->vLumFilterPos;
chrCtx->filter[0] = c->vChrFilter;
chrCtx->filter_size = c->vChrFilterSize;
chrCtx->filter_pos = c->vChrFilterPos;
lumCtx->isMMX = use_mmx;
chrCtx->isMMX = use_mmx;
if (yuv2packedX) {
if (c->yuv2packed1 && c->vLumFilterSize == 1 && c->vChrFilterSize <= 2)
lumCtx->pfn.yuv2packed1 = yuv2packed1;
else if (c->yuv2packed2 && c->vLumFilterSize == 2 && c->vChrFilterSize == 2)
lumCtx->pfn.yuv2packed2 = yuv2packed2;
lumCtx->yuv2packedX = yuv2packedX;
} else
lumCtx->pfn.yuv2anyX = yuv2anyX;
}
}