ffmpeg/libavfilter/drawutils.c

663 lines
24 KiB
C

/*
* Copyright 2011 Stefano Sabatini <stefano.sabatini-lala poste it>
* Copyright 2012 Nicolas George <nicolas.george normalesup org>
*
* 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 <string.h>
#include "libavutil/avassert.h"
#include "libavutil/avutil.h"
#include "libavutil/csp.h"
#include "libavutil/intreadwrite.h"
#include "libavutil/pixdesc.h"
#include "colorspace.h"
#include "drawutils.h"
#include "formats.h"
enum { RED = 0, GREEN, BLUE, ALPHA };
int ff_fill_rgba_map(uint8_t *rgba_map, enum AVPixelFormat pix_fmt)
{
const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(pix_fmt);
if (!(desc->flags & AV_PIX_FMT_FLAG_RGB))
return AVERROR(EINVAL);
if (desc->flags & AV_PIX_FMT_FLAG_BITSTREAM)
return AVERROR(EINVAL);
av_assert0(desc->nb_components == 3 + !!(desc->flags & AV_PIX_FMT_FLAG_ALPHA));
if (desc->flags & AV_PIX_FMT_FLAG_PLANAR) {
rgba_map[RED] = desc->comp[0].plane;
rgba_map[GREEN] = desc->comp[1].plane;
rgba_map[BLUE] = desc->comp[2].plane;
rgba_map[ALPHA] = (desc->flags & AV_PIX_FMT_FLAG_ALPHA) ? desc->comp[3].plane : 3;
} else {
int had0 = 0;
unsigned depthb = 0;
unsigned i;
for (i = 0; i < desc->nb_components; i++) {
/* all components must have same depth in bytes */
unsigned db = (desc->comp[i].depth + 7) / 8;
unsigned pos = desc->comp[i].offset / db;
if (depthb && (depthb != db))
return AVERROR(ENOSYS);
if (desc->comp[i].offset % db)
return AVERROR(ENOSYS);
had0 |= pos == 0;
rgba_map[i] = pos;
}
if (desc->nb_components == 3)
rgba_map[ALPHA] = had0 ? 3 : 0;
}
av_assert0(rgba_map[RED] != rgba_map[GREEN]);
av_assert0(rgba_map[GREEN] != rgba_map[BLUE]);
av_assert0(rgba_map[BLUE] != rgba_map[RED]);
av_assert0(rgba_map[RED] != rgba_map[ALPHA]);
av_assert0(rgba_map[GREEN] != rgba_map[ALPHA]);
av_assert0(rgba_map[BLUE] != rgba_map[ALPHA]);
return 0;
}
int ff_draw_init2(FFDrawContext *draw, enum AVPixelFormat format, enum AVColorSpace csp,
enum AVColorRange range, unsigned flags)
{
const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(format);
const AVLumaCoefficients *luma = NULL;
const AVComponentDescriptor *c;
unsigned i, nb_planes = 0;
int pixelstep[MAX_PLANES] = { 0 };
int depthb = 0;
if (!desc || !desc->name)
return AVERROR(EINVAL);
if (desc->flags & AV_PIX_FMT_FLAG_BE)
return AVERROR(ENOSYS);
if (desc->flags & ~(AV_PIX_FMT_FLAG_PLANAR | AV_PIX_FMT_FLAG_RGB | AV_PIX_FMT_FLAG_ALPHA))
return AVERROR(ENOSYS);
if (csp == AVCOL_SPC_UNSPECIFIED)
csp = (desc->flags & AV_PIX_FMT_FLAG_RGB) ? AVCOL_SPC_RGB : AVCOL_SPC_SMPTE170M;
if (!(desc->flags & AV_PIX_FMT_FLAG_RGB) && !(luma = av_csp_luma_coeffs_from_avcsp(csp)))
return AVERROR(EINVAL);
if (range == AVCOL_RANGE_UNSPECIFIED)
range = (format == AV_PIX_FMT_YUVJ420P || format == AV_PIX_FMT_YUVJ422P ||
format == AV_PIX_FMT_YUVJ444P || format == AV_PIX_FMT_YUVJ411P ||
format == AV_PIX_FMT_YUVJ440P || csp == AVCOL_SPC_RGB)
? AVCOL_RANGE_JPEG : AVCOL_RANGE_MPEG;
if (range != AVCOL_RANGE_JPEG && range != AVCOL_RANGE_MPEG)
return AVERROR(EINVAL);
for (i = 0; i < desc->nb_components; i++) {
int db;
c = &desc->comp[i];
/* for now, only 8-16 bits formats */
if (c->depth < 8 || c->depth > 16)
return AVERROR(ENOSYS);
if (c->plane >= MAX_PLANES)
return AVERROR(ENOSYS);
/* data must either be in the high or low bits, never middle */
if (c->shift && ((c->shift + c->depth) & 0x7))
return AVERROR(ENOSYS);
/* mixed >8 and <=8 depth */
db = (c->depth + 7) / 8;
if (depthb && (depthb != db))
return AVERROR(ENOSYS);
depthb = db;
if (db * (c->offset + 1) > 16)
return AVERROR(ENOSYS);
if (c->offset % db)
return AVERROR(ENOSYS);
/* strange interleaving */
if (pixelstep[c->plane] != 0 &&
pixelstep[c->plane] != c->step)
return AVERROR(ENOSYS);
if (pixelstep[c->plane] == 6 &&
c->depth == 16)
return AVERROR(ENOSYS);
pixelstep[c->plane] = c->step;
if (pixelstep[c->plane] >= 8)
return AVERROR(ENOSYS);
nb_planes = FFMAX(nb_planes, c->plane + 1);
}
memset(draw, 0, sizeof(*draw));
draw->desc = desc;
draw->format = format;
draw->nb_planes = nb_planes;
draw->range = range;
draw->csp = csp;
draw->flags = flags;
if (luma)
ff_fill_rgb2yuv_table(luma, draw->rgb2yuv);
memcpy(draw->pixelstep, pixelstep, sizeof(draw->pixelstep));
draw->hsub[1] = draw->hsub[2] = draw->hsub_max = desc->log2_chroma_w;
draw->vsub[1] = draw->vsub[2] = draw->vsub_max = desc->log2_chroma_h;
return 0;
}
int ff_draw_init(FFDrawContext *draw, enum AVPixelFormat format, unsigned flags)
{
return ff_draw_init2(draw, format, AVCOL_SPC_UNSPECIFIED, AVCOL_RANGE_UNSPECIFIED, flags);
}
void ff_draw_color(FFDrawContext *draw, FFDrawColor *color, const uint8_t rgba[4])
{
unsigned i;
double yuvad[4];
double rgbad[4];
const AVPixFmtDescriptor *desc = draw->desc;
if (rgba != color->rgba)
memcpy(color->rgba, rgba, sizeof(color->rgba));
memset(color->comp, 0, sizeof(color->comp));
for (int i = 0; i < 4; i++)
rgbad[i] = color->rgba[i] / 255.;
if (draw->desc->flags & AV_PIX_FMT_FLAG_RGB)
memcpy(yuvad, rgbad, sizeof(double) * 3);
else
ff_matrix_mul_3x3_vec(yuvad, rgbad, draw->rgb2yuv);
yuvad[3] = rgbad[3];
for (int i = 0; i < 3; i++) {
int chroma = (!(draw->desc->flags & AV_PIX_FMT_FLAG_RGB) && i > 0);
if (draw->range == AVCOL_RANGE_MPEG) {
yuvad[i] *= (chroma ? 224. : 219.) / 255.;
yuvad[i] += (chroma ? 128. : 16.) / 255.;
} else if (chroma) {
yuvad[i] += 0.5;
}
}
// Ensure we place the alpha appropriately for gray formats
if (desc->nb_components <= 2)
yuvad[1] = yuvad[3];
for (i = 0; i < desc->nb_components; i++) {
unsigned val = yuvad[i] * ((1 << (draw->desc->comp[i].depth + draw->desc->comp[i].shift)) - 1) + 0.5;
if (desc->comp[i].depth > 8)
color->comp[desc->comp[i].plane].u16[desc->comp[i].offset / 2] = val;
else
color->comp[desc->comp[i].plane].u8[desc->comp[i].offset] = val;
}
}
static uint8_t *pointer_at(FFDrawContext *draw, uint8_t *data[], int linesize[],
int plane, int x, int y)
{
return data[plane] +
(y >> draw->vsub[plane]) * linesize[plane] +
(x >> draw->hsub[plane]) * draw->pixelstep[plane];
}
void ff_copy_rectangle2(FFDrawContext *draw,
uint8_t *dst[], int dst_linesize[],
uint8_t *src[], int src_linesize[],
int dst_x, int dst_y, int src_x, int src_y,
int w, int h)
{
int plane, y, wp, hp;
uint8_t *p, *q;
for (plane = 0; plane < draw->nb_planes; plane++) {
p = pointer_at(draw, src, src_linesize, plane, src_x, src_y);
q = pointer_at(draw, dst, dst_linesize, plane, dst_x, dst_y);
wp = AV_CEIL_RSHIFT(w, draw->hsub[plane]) * draw->pixelstep[plane];
hp = AV_CEIL_RSHIFT(h, draw->vsub[plane]);
for (y = 0; y < hp; y++) {
memcpy(q, p, wp);
p += src_linesize[plane];
q += dst_linesize[plane];
}
}
}
void ff_fill_rectangle(FFDrawContext *draw, FFDrawColor *color,
uint8_t *dst[], int dst_linesize[],
int dst_x, int dst_y, int w, int h)
{
int plane, x, y, wp, hp;
uint8_t *p0, *p;
FFDrawColor color_tmp = *color;
for (plane = 0; plane < draw->nb_planes; plane++) {
p0 = pointer_at(draw, dst, dst_linesize, plane, dst_x, dst_y);
wp = AV_CEIL_RSHIFT(w, draw->hsub[plane]);
hp = AV_CEIL_RSHIFT(h, draw->vsub[plane]);
if (!hp)
return;
p = p0;
if (HAVE_BIGENDIAN && draw->desc->comp[0].depth > 8) {
for (x = 0; 2*x < draw->pixelstep[plane]; x++)
color_tmp.comp[plane].u16[x] = av_bswap16(color_tmp.comp[plane].u16[x]);
}
/* copy first line from color */
for (x = 0; x < wp; x++) {
memcpy(p, color_tmp.comp[plane].u8, draw->pixelstep[plane]);
p += draw->pixelstep[plane];
}
wp *= draw->pixelstep[plane];
/* copy next lines from first line */
p = p0 + dst_linesize[plane];
for (y = 1; y < hp; y++) {
memcpy(p, p0, wp);
p += dst_linesize[plane];
}
}
}
/**
* Clip interval [x; x+w[ within [0; wmax[.
* The resulting w may be negative if the final interval is empty.
* dx, if not null, return the difference between in and out value of x.
*/
static void clip_interval(int wmax, int *x, int *w, int *dx)
{
if (dx)
*dx = 0;
if (*x < 0) {
if (dx)
*dx = -*x;
*w += *x;
*x = 0;
}
if (*x + *w > wmax)
*w = wmax - *x;
}
/**
* Decompose w pixels starting at x
* into start + (w starting at x) + end
* with x and w aligned on multiples of 1<<sub.
*/
static void subsampling_bounds(int sub, int *x, int *w, int *start, int *end)
{
int mask = (1 << sub) - 1;
*start = (-*x) & mask;
*x += *start;
*start = FFMIN(*start, *w);
*w -= *start;
*end = *w & mask;
*w >>= sub;
}
/* If alpha is in the [ 0 ; 0x1010101 ] range,
then alpha * value is in the [ 0 ; 0xFFFFFFFF ] range,
and >> 24 gives a correct rounding. */
static void blend_line(uint8_t *dst, unsigned src, unsigned alpha,
int dx, int w, unsigned hsub, int left, int right)
{
unsigned asrc = alpha * src;
unsigned tau = 0x1010101 - alpha;
int x;
if (left) {
unsigned suba = (left * alpha) >> hsub;
*dst = (*dst * (0x1010101 - suba) + src * suba) >> 24;
dst += dx;
}
for (x = 0; x < w; x++) {
*dst = (*dst * tau + asrc) >> 24;
dst += dx;
}
if (right) {
unsigned suba = (right * alpha) >> hsub;
*dst = (*dst * (0x1010101 - suba) + src * suba) >> 24;
}
}
static void blend_line16(uint8_t *dst, unsigned src, unsigned alpha,
int dx, int w, unsigned hsub, int left, int right)
{
unsigned asrc = alpha * src;
unsigned tau = 0x10001 - alpha;
int x;
if (left) {
unsigned suba = (left * alpha) >> hsub;
uint16_t value = AV_RL16(dst);
AV_WL16(dst, (value * (0x10001 - suba) + src * suba) >> 16);
dst += dx;
}
for (x = 0; x < w; x++) {
uint16_t value = AV_RL16(dst);
AV_WL16(dst, (value * tau + asrc) >> 16);
dst += dx;
}
if (right) {
unsigned suba = (right * alpha) >> hsub;
uint16_t value = AV_RL16(dst);
AV_WL16(dst, (value * (0x10001 - suba) + src * suba) >> 16);
}
}
void ff_blend_rectangle(FFDrawContext *draw, FFDrawColor *color,
uint8_t *dst[], int dst_linesize[],
int dst_w, int dst_h,
int x0, int y0, int w, int h)
{
unsigned alpha, nb_planes, nb_comp, plane, comp;
int w_sub, h_sub, x_sub, y_sub, left, right, top, bottom, y;
uint8_t *p0, *p;
nb_comp = draw->desc->nb_components -
!!(draw->desc->flags & AV_PIX_FMT_FLAG_ALPHA && !(draw->flags & FF_DRAW_PROCESS_ALPHA));
/* TODO optimize if alpha = 0xFF */
clip_interval(dst_w, &x0, &w, NULL);
clip_interval(dst_h, &y0, &h, NULL);
if (w <= 0 || h <= 0 || !color->rgba[3])
return;
if (draw->desc->comp[0].depth <= 8) {
/* 0x10203 * alpha + 2 is in the [ 2 ; 0x1010101 - 2 ] range */
alpha = 0x10203 * color->rgba[3] + 0x2;
} else {
/* 0x101 * alpha is in the [ 2 ; 0x1001] range */
alpha = 0x101 * color->rgba[3] + 0x2;
}
nb_planes = draw->nb_planes - !!(draw->desc->flags & AV_PIX_FMT_FLAG_ALPHA && !(draw->flags & FF_DRAW_PROCESS_ALPHA));
nb_planes += !nb_planes;
for (plane = 0; plane < nb_planes; plane++) {
p0 = pointer_at(draw, dst, dst_linesize, plane, x0, y0);
w_sub = w;
h_sub = h;
x_sub = x0;
y_sub = y0;
subsampling_bounds(draw->hsub[plane], &x_sub, &w_sub, &left, &right);
subsampling_bounds(draw->vsub[plane], &y_sub, &h_sub, &top, &bottom);
for (comp = 0; comp < nb_comp; comp++) {
const int depth = draw->desc->comp[comp].depth;
const int offset = draw->desc->comp[comp].offset;
const int index = offset / ((depth + 7) / 8);
if (draw->desc->comp[comp].plane != plane)
continue;
p = p0 + offset;
if (top) {
if (depth <= 8) {
blend_line(p, color->comp[plane].u8[index], alpha >> 1,
draw->pixelstep[plane], w_sub,
draw->hsub[plane], left, right);
} else {
blend_line16(p, color->comp[plane].u16[index], alpha >> 1,
draw->pixelstep[plane], w_sub,
draw->hsub[plane], left, right);
}
p += dst_linesize[plane];
}
if (depth <= 8) {
for (y = 0; y < h_sub; y++) {
blend_line(p, color->comp[plane].u8[index], alpha,
draw->pixelstep[plane], w_sub,
draw->hsub[plane], left, right);
p += dst_linesize[plane];
}
} else {
for (y = 0; y < h_sub; y++) {
blend_line16(p, color->comp[plane].u16[index], alpha,
draw->pixelstep[plane], w_sub,
draw->hsub[plane], left, right);
p += dst_linesize[plane];
}
}
if (bottom) {
if (depth <= 8) {
blend_line(p, color->comp[plane].u8[index], alpha >> 1,
draw->pixelstep[plane], w_sub,
draw->hsub[plane], left, right);
} else {
blend_line16(p, color->comp[plane].u16[index], alpha >> 1,
draw->pixelstep[plane], w_sub,
draw->hsub[plane], left, right);
}
}
}
}
}
static void blend_pixel16(uint8_t *dst, unsigned src, unsigned alpha,
const uint8_t *mask, int mask_linesize, int l2depth,
unsigned w, unsigned h, unsigned shift, unsigned xm0)
{
unsigned xm, x, y, t = 0;
unsigned xmshf = 3 - l2depth;
unsigned xmmod = 7 >> l2depth;
unsigned mbits = (1 << (1 << l2depth)) - 1;
unsigned mmult = 255 / mbits;
uint16_t value = AV_RL16(dst);
for (y = 0; y < h; y++) {
xm = xm0;
for (x = 0; x < w; x++) {
t += ((mask[xm >> xmshf] >> ((~xm & xmmod) << l2depth)) & mbits)
* mmult;
xm++;
}
mask += mask_linesize;
}
alpha = (t >> shift) * alpha;
AV_WL16(dst, ((0x10001 - alpha) * value + alpha * src) >> 16);
}
static void blend_pixel(uint8_t *dst, unsigned src, unsigned alpha,
const uint8_t *mask, int mask_linesize, int l2depth,
unsigned w, unsigned h, unsigned shift, unsigned xm0)
{
unsigned xm, x, y, t = 0;
unsigned xmshf = 3 - l2depth;
unsigned xmmod = 7 >> l2depth;
unsigned mbits = (1 << (1 << l2depth)) - 1;
unsigned mmult = 255 / mbits;
for (y = 0; y < h; y++) {
xm = xm0;
for (x = 0; x < w; x++) {
t += ((mask[xm >> xmshf] >> ((~xm & xmmod) << l2depth)) & mbits)
* mmult;
xm++;
}
mask += mask_linesize;
}
alpha = (t >> shift) * alpha;
*dst = ((0x1010101 - alpha) * *dst + alpha * src) >> 24;
}
static void blend_line_hv16(uint8_t *dst, int dst_delta,
unsigned src, unsigned alpha,
const uint8_t *mask, int mask_linesize, int l2depth, int w,
unsigned hsub, unsigned vsub,
int xm, int left, int right, int hband)
{
int x;
if (left) {
blend_pixel16(dst, src, alpha, mask, mask_linesize, l2depth,
left, hband, hsub + vsub, xm);
dst += dst_delta;
xm += left;
}
for (x = 0; x < w; x++) {
blend_pixel16(dst, src, alpha, mask, mask_linesize, l2depth,
1 << hsub, hband, hsub + vsub, xm);
dst += dst_delta;
xm += 1 << hsub;
}
if (right)
blend_pixel16(dst, src, alpha, mask, mask_linesize, l2depth,
right, hband, hsub + vsub, xm);
}
static void blend_line_hv(uint8_t *dst, int dst_delta,
unsigned src, unsigned alpha,
const uint8_t *mask, int mask_linesize, int l2depth, int w,
unsigned hsub, unsigned vsub,
int xm, int left, int right, int hband)
{
int x;
if (left) {
blend_pixel(dst, src, alpha, mask, mask_linesize, l2depth,
left, hband, hsub + vsub, xm);
dst += dst_delta;
xm += left;
}
for (x = 0; x < w; x++) {
blend_pixel(dst, src, alpha, mask, mask_linesize, l2depth,
1 << hsub, hband, hsub + vsub, xm);
dst += dst_delta;
xm += 1 << hsub;
}
if (right)
blend_pixel(dst, src, alpha, mask, mask_linesize, l2depth,
right, hband, hsub + vsub, xm);
}
void ff_blend_mask(FFDrawContext *draw, FFDrawColor *color,
uint8_t *dst[], int dst_linesize[], int dst_w, int dst_h,
const uint8_t *mask, int mask_linesize, int mask_w, int mask_h,
int l2depth, unsigned endianness, int x0, int y0)
{
unsigned alpha, nb_planes, nb_comp, plane, comp;
int xm0, ym0, w_sub, h_sub, x_sub, y_sub, left, right, top, bottom, y;
uint8_t *p0, *p;
const uint8_t *m;
nb_comp = draw->desc->nb_components -
!!(draw->desc->flags & AV_PIX_FMT_FLAG_ALPHA && !(draw->flags & FF_DRAW_PROCESS_ALPHA));
clip_interval(dst_w, &x0, &mask_w, &xm0);
clip_interval(dst_h, &y0, &mask_h, &ym0);
mask += ym0 * mask_linesize;
if (mask_w <= 0 || mask_h <= 0 || !color->rgba[3])
return;
if (draw->desc->comp[0].depth <= 8) {
/* alpha is in the [ 0 ; 0x10203 ] range,
alpha * mask is in the [ 0 ; 0x1010101 - 4 ] range */
alpha = (0x10307 * color->rgba[3] + 0x3) >> 8;
} else {
alpha = (0x101 * color->rgba[3] + 0x2) >> 8;
}
nb_planes = draw->nb_planes - !!(draw->desc->flags & AV_PIX_FMT_FLAG_ALPHA && !(draw->flags & FF_DRAW_PROCESS_ALPHA));
nb_planes += !nb_planes;
for (plane = 0; plane < nb_planes; plane++) {
p0 = pointer_at(draw, dst, dst_linesize, plane, x0, y0);
w_sub = mask_w;
h_sub = mask_h;
x_sub = x0;
y_sub = y0;
subsampling_bounds(draw->hsub[plane], &x_sub, &w_sub, &left, &right);
subsampling_bounds(draw->vsub[plane], &y_sub, &h_sub, &top, &bottom);
for (comp = 0; comp < nb_comp; comp++) {
const int depth = draw->desc->comp[comp].depth;
const int offset = draw->desc->comp[comp].offset;
const int index = offset / ((depth + 7) / 8);
if (draw->desc->comp[comp].plane != plane)
continue;
p = p0 + offset;
m = mask;
if (top) {
if (depth <= 8) {
blend_line_hv(p, draw->pixelstep[plane],
color->comp[plane].u8[index], alpha,
m, mask_linesize, l2depth, w_sub,
draw->hsub[plane], draw->vsub[plane],
xm0, left, right, top);
} else {
blend_line_hv16(p, draw->pixelstep[plane],
color->comp[plane].u16[index], alpha,
m, mask_linesize, l2depth, w_sub,
draw->hsub[plane], draw->vsub[plane],
xm0, left, right, top);
}
p += dst_linesize[plane];
m += top * mask_linesize;
}
if (depth <= 8) {
for (y = 0; y < h_sub; y++) {
blend_line_hv(p, draw->pixelstep[plane],
color->comp[plane].u8[index], alpha,
m, mask_linesize, l2depth, w_sub,
draw->hsub[plane], draw->vsub[plane],
xm0, left, right, 1 << draw->vsub[plane]);
p += dst_linesize[plane];
m += mask_linesize << draw->vsub[plane];
}
} else {
for (y = 0; y < h_sub; y++) {
blend_line_hv16(p, draw->pixelstep[plane],
color->comp[plane].u16[index], alpha,
m, mask_linesize, l2depth, w_sub,
draw->hsub[plane], draw->vsub[plane],
xm0, left, right, 1 << draw->vsub[plane]);
p += dst_linesize[plane];
m += mask_linesize << draw->vsub[plane];
}
}
if (bottom) {
if (depth <= 8) {
blend_line_hv(p, draw->pixelstep[plane],
color->comp[plane].u8[index], alpha,
m, mask_linesize, l2depth, w_sub,
draw->hsub[plane], draw->vsub[plane],
xm0, left, right, bottom);
} else {
blend_line_hv16(p, draw->pixelstep[plane],
color->comp[plane].u16[index], alpha,
m, mask_linesize, l2depth, w_sub,
draw->hsub[plane], draw->vsub[plane],
xm0, left, right, bottom);
}
}
}
}
}
int ff_draw_round_to_sub(FFDrawContext *draw, int sub_dir, int round_dir,
int value)
{
unsigned shift = sub_dir ? draw->vsub_max : draw->hsub_max;
if (!shift)
return value;
if (round_dir >= 0)
value += round_dir ? (1 << shift) - 1 : 1 << (shift - 1);
return (value >> shift) << shift;
}
AVFilterFormats *ff_draw_supported_pixel_formats(unsigned flags)
{
enum AVPixelFormat i;
FFDrawContext draw;
AVFilterFormats *fmts = NULL;
int ret;
for (i = 0; av_pix_fmt_desc_get(i); i++)
if (ff_draw_init(&draw, i, flags) >= 0 &&
(ret = ff_add_format(&fmts, i)) < 0)
return NULL;
return fmts;
}