As mentioned here
(https://ffmpeg.org/pipermail/ffmpeg-devel/2025-June/344593.html), this is the
first step of a 2 steps patch: move the interpolation code out of the
vf_perspective filter so that we can use it in the zoompan filter and apply
scale/crop floating point precision there.
I've moved the whole " ff_filter_execute " logic in these new files since we're
going to use the exact same logic in zoompan.
Signed-off-by: Quentin Renard <contact-git...@asticode.com>
---
libavfilter/Makefile | 2 +-
libavfilter/perspective.c | 404 +++++++++++++++++++++++++++++++++++
libavfilter/perspective.h | 66 ++++++
libavfilter/vf_perspective.c | 372 +++-----------------------------
4 files changed, 496 insertions(+), 348 deletions(-)
create mode 100644 libavfilter/perspective.c
create mode 100644 libavfilter/perspective.h
diff --git a/libavfilter/Makefile b/libavfilter/Makefile
index 97f8f17272..7c6dfcf4bf 100644
--- a/libavfilter/Makefile
+++ b/libavfilter/Makefile
@@ -426,7 +426,7 @@ OBJS-$(CONFIG_PAD_OPENCL_FILTER) +=
vf_pad_opencl.o opencl.o opencl/
OBJS-$(CONFIG_PALETTEGEN_FILTER) += vf_palettegen.o palette.o
OBJS-$(CONFIG_PALETTEUSE_FILTER) += vf_paletteuse.o framesync.o
palette.o
OBJS-$(CONFIG_PERMS_FILTER) += f_perms.o
-OBJS-$(CONFIG_PERSPECTIVE_FILTER) += vf_perspective.o
+OBJS-$(CONFIG_PERSPECTIVE_FILTER) += vf_perspective.o perspective.o
OBJS-$(CONFIG_PHASE_FILTER) += vf_phase.o
OBJS-$(CONFIG_PHOTOSENSITIVITY_FILTER) += vf_photosensitivity.o
OBJS-$(CONFIG_PIXDESCTEST_FILTER) += vf_pixdesctest.o
diff --git a/libavfilter/perspective.c b/libavfilter/perspective.c
new file mode 100644
index 0000000000..ab200f8532
--- /dev/null
+++ b/libavfilter/perspective.c
@@ -0,0 +1,404 @@
+/*
+ * Copyright (c) 2002 Michael Niedermayer <michae...@gmx.at>
+ * Copyright (c) 2013 Paul B Mahol
+ * Copyright (c) 2025 Quentin Renard
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU 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 "libavutil/avassert.h"
+#include "libavutil/imgutils.h"
+#include "libavutil/mem.h"
+#include "filters.h"
+#include "perspective.h"
+
+static inline double get_coeff(double d)
+{
+ double coeff, A = -0.60;
+
+ d = fabs(d);
+
+ if (d < 1.0)
+ coeff = (1.0 - (A + 3.0) * d * d + (A + 2.0) * d * d * d);
+ else if (d < 2.0)
+ coeff = (-4.0 * A + 8.0 * A * d - 5.0 * A * d * d + A * d * d * d);
+ else
+ coeff = 0.0;
+
+ return coeff;
+}
+
+typedef struct ThreadData {
+ PerspectiveResampleContext *s;
+ uint8_t *dst;
+ int dst_linesize;
+ uint8_t *src;
+ int src_linesize;
+ int w, h;
+ int hsub, vsub;
+} ThreadData;
+
+static int perspective_resample_cubic(AVFilterContext *ctx, void *arg,
+ int job, int nb_jobs)
+{
+ ThreadData *td = arg;
+ uint8_t *dst = td->dst;
+ int dst_linesize = td->dst_linesize;
+ uint8_t *src = td->src;
+ int src_linesize = td->src_linesize;
+ int w = td->w;
+ int h = td->h;
+ int hsub = td->hsub;
+ int vsub = td->vsub;
+ int start = (h * job) / nb_jobs;
+ int end = (h * (job+1)) / nb_jobs;
+ const int linesize = td->s->linesize[0];
+ int x, y;
+
+ for (y = start; y < end; y++) {
+ int sy = y << vsub;
+ for (x = 0; x < w; x++) {
+ int u, v, subU, subV, sum, sx;
+
+ sx = x << hsub;
+ u = td->s->pv[sx + sy * linesize][0] >> hsub;
+ v = td->s->pv[sx + sy * linesize][1] >> vsub;
+ subU = u & (PERSPECTIVE_RESAMPLE_SUB_PIXELS - 1);
+ subV = v & (PERSPECTIVE_RESAMPLE_SUB_PIXELS - 1);
+ u >>= PERSPECTIVE_RESAMPLE_SUB_PIXEL_BITS;
+ v >>= PERSPECTIVE_RESAMPLE_SUB_PIXEL_BITS;
+
+ if (u > 0 && v > 0 && u < w - 2 && v < h - 2){
+ const int index = u + v*src_linesize;
+ const int a = td->s->coeff[subU][0];
+ const int b = td->s->coeff[subU][1];
+ const int c = td->s->coeff[subU][2];
+ const int d = td->s->coeff[subU][3];
+
+ sum = td->s->coeff[subV][0] * (a * src[index - 1 -
src_linesize] + b * src[index - 0 - src_linesize] +
+ c * src[index + 1 -
src_linesize] + d * src[index + 2 - src_linesize]) +
+ td->s->coeff[subV][1] * (a * src[index - 1
] + b * src[index - 0 ] +
+ c * src[index + 1
] + d * src[index + 2 ]) +
+ td->s->coeff[subV][2] * (a * src[index - 1 +
src_linesize] + b * src[index - 0 + src_linesize] +
+ c * src[index + 1 +
src_linesize] + d * src[index + 2 + src_linesize]) +
+ td->s->coeff[subV][3] * (a * src[index - 1 + 2 *
src_linesize] + b * src[index - 0 + 2 * src_linesize] +
+ c * src[index + 1 + 2 *
src_linesize] + d * src[index + 2 + 2 * src_linesize]);
+ } else {
+ int dx, dy;
+
+ sum = 0;
+
+ for (dy = 0; dy < 4; dy++) {
+ int iy = v + dy - 1;
+
+ if (iy < 0)
+ iy = 0;
+ else if (iy >= h)
+ iy = h-1;
+ for (dx = 0; dx < 4; dx++) {
+ int ix = u + dx - 1;
+
+ if (ix < 0)
+ ix = 0;
+ else if (ix >= w)
+ ix = w - 1;
+
+ sum += td->s->coeff[subU][dx] * td->s->coeff[subV][dy]
* src[ ix + iy * src_linesize];
+ }
+ }
+ }
+
+ sum = (sum + (1<<(PERSPECTIVE_RESAMPLE_COEFF_BITS * 2 - 1))) >>
(PERSPECTIVE_RESAMPLE_COEFF_BITS * 2);
+ sum = av_clip_uint8(sum);
+ dst[x + y * dst_linesize] = sum;
+ }
+ }
+ return 0;
+}
+
+static int perspective_resample_linear(AVFilterContext *ctx, void *arg,
+ int job, int nb_jobs)
+{
+ ThreadData *td = arg;
+ uint8_t *dst = td->dst;
+ int dst_linesize = td->dst_linesize;
+ uint8_t *src = td->src;
+ int src_linesize = td->src_linesize;
+ int w = td->w;
+ int h = td->h;
+ int hsub = td->hsub;
+ int vsub = td->vsub;
+ int start = (h * job) / nb_jobs;
+ int end = (h * (job+1)) / nb_jobs;
+ const int linesize = td->s->linesize[0];
+ int x, y;
+
+ for (y = start; y < end; y++){
+ int sy = y << vsub;
+ for (x = 0; x < w; x++){
+ int u, v, subU, subV, sum, sx, index, subUI, subVI;
+
+ sx = x << hsub;
+ u = td->s->pv[sx + sy * linesize][0] >> hsub;
+ v = td->s->pv[sx + sy * linesize][1] >> vsub;
+ subU = u & (PERSPECTIVE_RESAMPLE_SUB_PIXELS - 1);
+ subV = v & (PERSPECTIVE_RESAMPLE_SUB_PIXELS - 1);
+ u >>= PERSPECTIVE_RESAMPLE_SUB_PIXEL_BITS;
+ v >>= PERSPECTIVE_RESAMPLE_SUB_PIXEL_BITS;
+
+ index = u + v * src_linesize;
+ subUI = PERSPECTIVE_RESAMPLE_SUB_PIXELS - subU;
+ subVI = PERSPECTIVE_RESAMPLE_SUB_PIXELS - subV;
+
+ if ((unsigned)u < (unsigned)(w - 1)){
+ if((unsigned)v < (unsigned)(h - 1)){
+ sum = subVI * (subUI * src[index] + subU * src[index + 1])
+
+ subV * (subUI * src[index + src_linesize] + subU *
src[index + src_linesize + 1]);
+ sum = (sum + (1 << (PERSPECTIVE_RESAMPLE_SUB_PIXEL_BITS *
2 - 1)))>> (PERSPECTIVE_RESAMPLE_SUB_PIXEL_BITS * 2);
+ } else {
+ if (v < 0)
+ v = 0;
+ else
+ v = h - 1;
+ index = u + v * src_linesize;
+ sum = subUI * src[index] + subU * src[index + 1];
+ sum = (sum + (1 << (PERSPECTIVE_RESAMPLE_SUB_PIXEL_BITS
- 1))) >> PERSPECTIVE_RESAMPLE_SUB_PIXEL_BITS;
+ }
+ } else {
+ if (u < 0)
+ u = 0;
+ else
+ u = w - 1;
+ if ((unsigned)v < (unsigned)(h - 1)){
+ index = u + v * src_linesize;
+ sum = subVI * src[index] + subV * src[index +
src_linesize];
+ sum = (sum + (1 << (PERSPECTIVE_RESAMPLE_SUB_PIXEL_BITS
- 1))) >> PERSPECTIVE_RESAMPLE_SUB_PIXEL_BITS;
+ } else {
+ if (v < 0)
+ v = 0;
+ else
+ v = h - 1;
+ index = u + v * src_linesize;
+ sum = src[index];
+ }
+ }
+
+ sum = av_clip_uint8(sum);
+ dst[x + y * dst_linesize] = sum;
+ }
+ }
+ return 0;
+}
+
+PerspectiveResampleContext* perspective_resample_context_alloc(int
interpolation, int sense)
+{
+ int i, j;
+
+ PerspectiveResampleContext *s = av_malloc(sizeof(*s));
+
+ if (!s)
+ return NULL;
+
+ s->pix_fmt = AV_PIX_FMT_NONE;
+ s->sense = sense;
+
+ switch (interpolation) {
+ case PERSPECTIVE_RESAMPLE_INTERPOLATION_LINEAR: s->resample =
perspective_resample_linear; break;
+ case PERSPECTIVE_RESAMPLE_INTERPOLATION_CUBIC: s->resample =
perspective_resample_cubic; break;
+ }
+
+ for (i = 0; i < PERSPECTIVE_RESAMPLE_SUB_PIXELS; i++){
+ double d = i / (double)PERSPECTIVE_RESAMPLE_SUB_PIXELS;
+ double temp[4];
+ double sum = 0;
+
+ for (j = 0; j < 4; j++)
+ temp[j] = get_coeff(j - d - 1);
+
+ for (j = 0; j < 4; j++)
+ sum += temp[j];
+
+ for (j = 0; j < 4; j++)
+ s->coeff[i][j] = lrint((1 << PERSPECTIVE_RESAMPLE_COEFF_BITS) *
temp[j] / sum);
+ }
+
+ return s;
+}
+
+void perspective_resample_context_free(PerspectiveResampleContext **s)
+{
+ if (!s || !*s)
+ return;
+
+ av_freep(&(*s)->pv);
+ av_freep(s);
+}
+
+static int luts_parameters_changed(PerspectiveResampleContext *s, int w, int
h, double ref[4][2])
+{
+ if (s->w != w || s->h != h)
+ return 1;
+
+ int i, j;
+ for (i = 0; i < 4; i++) {
+ for (j = 0; j < 2; j++) {
+ if (ref[i][j] != s->ref[i][j])
+ return 1;
+ }
+ }
+
+ return 0;
+}
+
+static int calc_luts(PerspectiveResampleContext *s, int w, int h, double
ref[4][2])
+{
+ double x0, x1, x2, x3, x4, x5, x6, x7, x8, q;
+ double t0, t1, t2, t3;
+ int x, y;
+
+ switch (s->sense) {
+ case PERSPECTIVE_RESAMPLE_SENSE_SOURCE:
+ x6 = ((ref[0][0] - ref[1][0] - ref[2][0] + ref[3][0]) *
+ (ref[2][1] - ref[3][1]) -
+ ( ref[0][1] - ref[1][1] - ref[2][1] + ref[3][1]) *
+ (ref[2][0] - ref[3][0])) * h;
+ x7 = ((ref[0][1] - ref[1][1] - ref[2][1] + ref[3][1]) *
+ (ref[1][0] - ref[3][0]) -
+ ( ref[0][0] - ref[1][0] - ref[2][0] + ref[3][0]) *
+ (ref[1][1] - ref[3][1])) * w;
+ q = ( ref[1][0] - ref[3][0]) * (ref[2][1] - ref[3][1]) -
+ ( ref[2][0] - ref[3][0]) * (ref[1][1] - ref[3][1]);
+
+ x0 = q * (ref[1][0] - ref[0][0]) * h + x6 * ref[1][0];
+ x1 = q * (ref[2][0] - ref[0][0]) * w + x7 * ref[2][0];
+ x2 = q * ref[0][0] * w * h;
+ x3 = q * (ref[1][1] - ref[0][1]) * h + x6 * ref[1][1];
+ x4 = q * (ref[2][1] - ref[0][1]) * w + x7 * ref[2][1];
+ x5 = q * ref[0][1] * w * h;
+ x8 = q * w * h;
+ break;
+ case PERSPECTIVE_RESAMPLE_SENSE_DESTINATION:
+ t0 = ref[0][0] * (ref[3][1] - ref[1][1]) +
+ ref[1][0] * (ref[0][1] - ref[3][1]) +
+ ref[3][0] * (ref[1][1] - ref[0][1]);
+ t1 = ref[1][0] * (ref[2][1] - ref[3][1]) +
+ ref[2][0] * (ref[3][1] - ref[1][1]) +
+ ref[3][0] * (ref[1][1] - ref[2][1]);
+ t2 = ref[0][0] * (ref[3][1] - ref[2][1]) +
+ ref[2][0] * (ref[0][1] - ref[3][1]) +
+ ref[3][0] * (ref[2][1] - ref[0][1]);
+ t3 = ref[0][0] * (ref[1][1] - ref[2][1]) +
+ ref[1][0] * (ref[2][1] - ref[0][1]) +
+ ref[2][0] * (ref[0][1] - ref[1][1]);
+
+ x0 = t0 * t1 * w * (ref[2][1] - ref[0][1]);
+ x1 = t0 * t1 * w * (ref[0][0] - ref[2][0]);
+ x2 = t0 * t1 * w * (ref[0][1] * ref[2][0] - ref[0][0] * ref[2][1]);
+ x3 = t1 * t2 * h * (ref[1][1] - ref[0][1]);
+ x4 = t1 * t2 * h * (ref[0][0] - ref[1][0]);
+ x5 = t1 * t2 * h * (ref[0][1] * ref[1][0] - ref[0][0] * ref[1][1]);
+ x6 = t1 * t2 * (ref[1][1] - ref[0][1]) +
+ t0 * t3 * (ref[2][1] - ref[3][1]);
+ x7 = t1 * t2 * (ref[0][0] - ref[1][0]) +
+ t0 * t3 * (ref[3][0] - ref[2][0]);
+ x8 = t1 * t2 * (ref[0][1] * ref[1][0] - ref[0][0] * ref[1][1]) +
+ t0 * t3 * (ref[2][0] * ref[3][1] - ref[2][1] * ref[3][0]);
+ break;
+ default:
+ av_assert0(0);
+ }
+
+ for (y = 0; y < h; y++){
+ for (x = 0; x < w; x++){
+ int u, v;
+
+ u = lrint(PERSPECTIVE_RESAMPLE_SUB_PIXELS * (x0 * x + x1 * y
+ x2) /
+ (x6 * x + x7 * y + x8));
+ v = lrint(PERSPECTIVE_RESAMPLE_SUB_PIXELS * (x3 * x + x4 * y
+ x5) /
+ (x6 * x + x7 * y + x8));
+
+ s->pv[x + y * w][0] = u;
+ s->pv[x + y * w][1] = v;
+ }
+ }
+
+ return 0;
+}
+
+int perspective_resample_config_props(PerspectiveResampleContext *s, int w,
int h, int pix_fmt, double ref[4][2])
+{
+ int i, j, ret;
+
+ if (s->pix_fmt != pix_fmt) {
+ s->desc = av_pix_fmt_desc_get(pix_fmt);
+ s->hsub = s->desc->log2_chroma_w;
+ s->vsub = s->desc->log2_chroma_h;
+ s->nb_planes = av_pix_fmt_count_planes(pix_fmt);
+ }
+
+ if (s->pix_fmt != pix_fmt || s->w != w) {
+ if ((ret = av_image_fill_linesizes(s->linesize, pix_fmt, w)) < 0)
+ return ret;
+ }
+
+ if (s->pix_fmt != pix_fmt || s->h != h) {
+ s->height[1] = s->height[2] = AV_CEIL_RSHIFT(h,
s->desc->log2_chroma_h);
+ s->height[0] = s->height[3] = h;
+ }
+
+ if (s->w != w || s->h !=h) {
+ s->pv = av_realloc_f(s->pv, w * h, 2 * sizeof(*s->pv));
+ if (!s->pv)
+ return AVERROR(ENOMEM);
+ }
+
+ if (luts_parameters_changed(s, w, h, ref)) {
+ if ((ret = calc_luts(s, w, h, ref)) < 0)
+ return ret;
+ }
+
+ s->w = w;
+ s->h = h;
+ s->pix_fmt = pix_fmt;
+ for (i = 0; i < 4; i++) {
+ for (j = 0; j < 2; j++) {
+ s->ref[i][j] = ref[i][j];
+ }
+ }
+ return 0;
+}
+
+void perspective_resample(PerspectiveResampleContext *s, AVFilterContext *ctx,
AVFrame *src, AVFrame *dst)
+{
+ int plane;
+
+ for (plane = 0; plane < s->nb_planes; plane++) {
+ int hsub = plane == 1 || plane == 2 ? s->hsub : 0;
+ int vsub = plane == 1 || plane == 2 ? s->vsub : 0;
+ ThreadData td = {.s = s,
+ .dst = dst->data[plane],
+ .dst_linesize = dst->linesize[plane],
+ .src = src->data[plane],
+ .src_linesize = src->linesize[plane],
+ .w = s->linesize[plane],
+ .h = s->height[plane],
+ .hsub = hsub,
+ .vsub = vsub };
+ ff_filter_execute(ctx, s->resample, &td, NULL,
+ FFMIN(td.h, ff_filter_get_nb_threads(ctx)));
+ }
+}
diff --git a/libavfilter/perspective.h b/libavfilter/perspective.h
new file mode 100644
index 0000000000..445c5cdac3
--- /dev/null
+++ b/libavfilter/perspective.h
@@ -0,0 +1,66 @@
+/*
+ * Copyright (c) 2002 Michael Niedermayer <michae...@gmx.at>
+ * Copyright (c) 2013 Paul B Mahol
+ * Copyright (c) 2025 Quentin Renard
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU 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
+ */
+
+#ifndef AVFILTER_PERSPECTIVE_H
+#define AVFILTER_PERSPECTIVE_H
+
+#include "avfilter.h"
+
+#define PERSPECTIVE_RESAMPLE_SUB_PIXEL_BITS 8
+#define PERSPECTIVE_RESAMPLE_SUB_PIXELS (1 <<
PERSPECTIVE_RESAMPLE_SUB_PIXEL_BITS)
+#define PERSPECTIVE_RESAMPLE_COEFF_BITS 11
+
+typedef struct PerspectiveResampleContext {
+ int sense;
+ int w, h, pix_fmt;
+ const AVPixFmtDescriptor *desc;
+ double ref[4][2];
+ int32_t (*pv)[2];
+ int32_t coeff[PERSPECTIVE_RESAMPLE_SUB_PIXELS][4];
+ int linesize[4];
+ int height[4];
+ int hsub, vsub;
+ int nb_planes;
+
+ int (*resample)(AVFilterContext *ctx,
+ void *arg, int job, int nb_jobs);
+} PerspectiveResampleContext;
+
+typedef enum {
+ PERSPECTIVE_RESAMPLE_INTERPOLATION_LINEAR = 0,
+ PERSPECTIVE_RESAMPLE_INTERPOLATION_CUBIC = 1,
+} PerspectiveResampleInterpolation;
+
+typedef enum {
+ PERSPECTIVE_RESAMPLE_SENSE_SOURCE = 0, ///< coordinates give
locations in source of corners of destination.
+ PERSPECTIVE_RESAMPLE_SENSE_DESTINATION = 1, ///< coordinates give
locations in destination of corners of source.
+} PerspectiveResampleSense;
+
+PerspectiveResampleContext* perspective_resample_context_alloc(int
interpolation, int sense);
+
+void perspective_resample_context_free(PerspectiveResampleContext **s);
+
+int perspective_resample_config_props(PerspectiveResampleContext *s, int w,
int h, int pix_fmt, double ref[4][2]);
+
+void perspective_resample(PerspectiveResampleContext *s, AVFilterContext *ctx,
AVFrame *src, AVFrame *dst);
+
+#endif /* AVFILTER_PERSPECTIVE_H */
\ No newline at end of file
diff --git a/libavfilter/vf_perspective.c b/libavfilter/vf_perspective.c
index 58510f6f13..f5766eed7a 100644
--- a/libavfilter/vf_perspective.c
+++ b/libavfilter/vf_perspective.c
@@ -1,6 +1,7 @@
/*
* Copyright (c) 2002 Michael Niedermayer <michae...@gmx.at>
* Copyright (c) 2013 Paul B Mahol
+ * Copyright (c) 2025 Quentin Renard
*
* This file is part of FFmpeg.
*
@@ -27,41 +28,21 @@
#include "libavutil/opt.h"
#include "avfilter.h"
#include "filters.h"
+#include "perspective.h"
#include "video.h"
-#define SUB_PIXEL_BITS 8
-#define SUB_PIXELS (1 << SUB_PIXEL_BITS)
-#define COEFF_BITS 11
-
-#define LINEAR 0
-#define CUBIC 1
-
typedef struct PerspectiveContext {
const AVClass *class;
char *expr_str[4][2];
- double ref[4][2];
- int32_t (*pv)[2];
- int32_t coeff[SUB_PIXELS][4];
+ int eval_mode;
int interpolation;
- int linesize[4];
- int height[4];
- int hsub, vsub;
- int nb_planes;
int sense;
- int eval_mode;
-
- int (*perspective)(AVFilterContext *ctx,
- void *arg, int job, int nb_jobs);
+ PerspectiveResampleContext *r;
} PerspectiveContext;
#define OFFSET(x) offsetof(PerspectiveContext, x)
#define FLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM
-enum PERSPECTIVESense {
- PERSPECTIVE_SENSE_SOURCE = 0, ///< coordinates give locations in
source of corners of destination.
- PERSPECTIVE_SENSE_DESTINATION = 1, ///< coordinates give locations in
destination of corners of source.
-};
-
enum EvalMode {
EVAL_MODE_INIT,
EVAL_MODE_FRAME,
@@ -77,14 +58,14 @@ static const AVOption perspective_options[] = {
{ "y2", "set bottom left y coordinate", OFFSET(expr_str[2][1]),
AV_OPT_TYPE_STRING, {.str="H"}, 0, 0, FLAGS },
{ "x3", "set bottom right x coordinate", OFFSET(expr_str[3][0]),
AV_OPT_TYPE_STRING, {.str="W"}, 0, 0, FLAGS },
{ "y3", "set bottom right y coordinate", OFFSET(expr_str[3][1]),
AV_OPT_TYPE_STRING, {.str="H"}, 0, 0, FLAGS },
- { "interpolation", "set interpolation", OFFSET(interpolation),
AV_OPT_TYPE_INT, {.i64=LINEAR}, 0, 1, FLAGS, .unit = "interpolation" },
- { "linear", "", 0, AV_OPT_TYPE_CONST, {.i64=LINEAR}, 0, 0, FLAGS,
.unit = "interpolation" },
- { "cubic", "", 0, AV_OPT_TYPE_CONST, {.i64=CUBIC}, 0, 0, FLAGS,
.unit = "interpolation" },
- { "sense", "specify the sense of the coordinates", OFFSET(sense),
AV_OPT_TYPE_INT, {.i64=PERSPECTIVE_SENSE_SOURCE}, 0, 1, FLAGS, .unit = "sense"},
+ { "interpolation", "set interpolation", OFFSET(interpolation),
AV_OPT_TYPE_INT, {.i64=PERSPECTIVE_RESAMPLE_INTERPOLATION_LINEAR}, 0, 1, FLAGS,
.unit = "interpolation" },
+ { "linear", "", 0, AV_OPT_TYPE_CONST,
{.i64=PERSPECTIVE_RESAMPLE_INTERPOLATION_LINEAR}, 0, 0, FLAGS, .unit =
"interpolation" },
+ { "cubic", "", 0, AV_OPT_TYPE_CONST,
{.i64=PERSPECTIVE_RESAMPLE_INTERPOLATION_CUBIC}, 0, 0, FLAGS, .unit =
"interpolation" },
+ { "sense", "specify the sense of the coordinates", OFFSET(sense),
AV_OPT_TYPE_INT, {.i64=PERSPECTIVE_RESAMPLE_SENSE_SOURCE}, 0, 1, FLAGS, .unit =
"sense"},
{ "source", "specify locations in source to send to corners in
destination",
- 0, AV_OPT_TYPE_CONST, {.i64=PERSPECTIVE_SENSE_SOURCE}, 0, 0,
FLAGS, .unit = "sense"},
+ 0, AV_OPT_TYPE_CONST,
{.i64=PERSPECTIVE_RESAMPLE_SENSE_SOURCE}, 0, 0, FLAGS, .unit = "sense"},
{ "destination", "specify locations in destination to send corners
of source",
- 0, AV_OPT_TYPE_CONST, {.i64=PERSPECTIVE_SENSE_DESTINATION}, 0,
0, FLAGS, .unit = "sense"},
+ 0, AV_OPT_TYPE_CONST,
{.i64=PERSPECTIVE_RESAMPLE_SENSE_DESTINATION}, 0, 0, FLAGS, .unit = "sense"},
{ "eval", "specify when to evaluate expressions", OFFSET(eval_mode),
AV_OPT_TYPE_INT, {.i64 = EVAL_MODE_INIT}, 0, EVAL_MODE_NB-1, FLAGS, .unit =
"eval" },
{ "init", "eval expressions once during initialization", 0,
AV_OPT_TYPE_CONST, {.i64=EVAL_MODE_INIT}, .flags = FLAGS, .unit = "eval" },
{ "frame", "eval expressions per-frame", 0,
AV_OPT_TYPE_CONST, {.i64=EVAL_MODE_FRAME}, .flags = FLAGS, .unit = "eval" },
@@ -101,47 +82,28 @@ static const enum AVPixelFormat pix_fmts[] = {
AV_PIX_FMT_GBRP, AV_PIX_FMT_GBRAP, AV_PIX_FMT_GRAY8, AV_PIX_FMT_NONE
};
-static inline double get_coeff(double d)
-{
- double coeff, A = -0.60;
-
- d = fabs(d);
-
- if (d < 1.0)
- coeff = (1.0 - (A + 3.0) * d * d + (A + 2.0) * d * d * d);
- else if (d < 2.0)
- coeff = (-4.0 * A + 8.0 * A * d - 5.0 * A * d * d + A * d * d * d);
- else
- coeff = 0.0;
-
- return coeff;
-}
-
static const char *const var_names[] = { "W", "H", "in", "on",
NULL };
enum { VAR_W, VAR_H, VAR_IN, VAR_ON,
VAR_VARS_NB };
-static int calc_persp_luts(AVFilterContext *ctx, AVFilterLink *inlink)
+static int config_props(AVFilterContext *ctx, int w, int h, int pix_fmt)
{
- FilterLink *inl = ff_filter_link(inlink);
PerspectiveContext *s = ctx->priv;
+ AVFilterLink *inlink = ctx->inputs[0];
+ FilterLink *inl = ff_filter_link(inlink);
AVFilterLink *outlink = ctx->outputs[0];
FilterLink *outl = ff_filter_link(outlink);
- double (*ref)[2] = s->ref;
+ double ref[4][2];
- double values[VAR_VARS_NB] = { [VAR_W] = inlink->w, [VAR_H] = inlink->h,
+ double values[VAR_VARS_NB] = { [VAR_W] = w, [VAR_H] = h,
[VAR_IN] = inl->frame_count_out + 1,
[VAR_ON] = outl->frame_count_in + 1 };
- const int h = values[VAR_H];
- const int w = values[VAR_W];
- double x0, x1, x2, x3, x4, x5, x6, x7, x8, q;
- double t0, t1, t2, t3;
- int x, y, i, j, ret;
+ int i, j, ret;
for (i = 0; i < 4; i++) {
for (j = 0; j < 2; j++) {
if (!s->expr_str[i][j])
return AVERROR(EINVAL);
- ret = av_expr_parse_and_eval(&s->ref[i][j], s->expr_str[i][j],
+ ret = av_expr_parse_and_eval(&ref[i][j], s->expr_str[i][j],
var_names, &values[0],
NULL, NULL, NULL, NULL,
0, 0, ctx);
@@ -150,291 +112,21 @@ static int calc_persp_luts(AVFilterContext *ctx,
AVFilterLink *inlink)
}
}
- switch (s->sense) {
- case PERSPECTIVE_SENSE_SOURCE:
- x6 = ((ref[0][0] - ref[1][0] - ref[2][0] + ref[3][0]) *
- (ref[2][1] - ref[3][1]) -
- ( ref[0][1] - ref[1][1] - ref[2][1] + ref[3][1]) *
- (ref[2][0] - ref[3][0])) * h;
- x7 = ((ref[0][1] - ref[1][1] - ref[2][1] + ref[3][1]) *
- (ref[1][0] - ref[3][0]) -
- ( ref[0][0] - ref[1][0] - ref[2][0] + ref[3][0]) *
- (ref[1][1] - ref[3][1])) * w;
- q = ( ref[1][0] - ref[3][0]) * (ref[2][1] - ref[3][1]) -
- ( ref[2][0] - ref[3][0]) * (ref[1][1] - ref[3][1]);
-
- x0 = q * (ref[1][0] - ref[0][0]) * h + x6 * ref[1][0];
- x1 = q * (ref[2][0] - ref[0][0]) * w + x7 * ref[2][0];
- x2 = q * ref[0][0] * w * h;
- x3 = q * (ref[1][1] - ref[0][1]) * h + x6 * ref[1][1];
- x4 = q * (ref[2][1] - ref[0][1]) * w + x7 * ref[2][1];
- x5 = q * ref[0][1] * w * h;
- x8 = q * w * h;
- break;
- case PERSPECTIVE_SENSE_DESTINATION:
- t0 = ref[0][0] * (ref[3][1] - ref[1][1]) +
- ref[1][0] * (ref[0][1] - ref[3][1]) +
- ref[3][0] * (ref[1][1] - ref[0][1]);
- t1 = ref[1][0] * (ref[2][1] - ref[3][1]) +
- ref[2][0] * (ref[3][1] - ref[1][1]) +
- ref[3][0] * (ref[1][1] - ref[2][1]);
- t2 = ref[0][0] * (ref[3][1] - ref[2][1]) +
- ref[2][0] * (ref[0][1] - ref[3][1]) +
- ref[3][0] * (ref[2][1] - ref[0][1]);
- t3 = ref[0][0] * (ref[1][1] - ref[2][1]) +
- ref[1][0] * (ref[2][1] - ref[0][1]) +
- ref[2][0] * (ref[0][1] - ref[1][1]);
-
- x0 = t0 * t1 * w * (ref[2][1] - ref[0][1]);
- x1 = t0 * t1 * w * (ref[0][0] - ref[2][0]);
- x2 = t0 * t1 * w * (ref[0][1] * ref[2][0] - ref[0][0] * ref[2][1]);
- x3 = t1 * t2 * h * (ref[1][1] - ref[0][1]);
- x4 = t1 * t2 * h * (ref[0][0] - ref[1][0]);
- x5 = t1 * t2 * h * (ref[0][1] * ref[1][0] - ref[0][0] * ref[1][1]);
- x6 = t1 * t2 * (ref[1][1] - ref[0][1]) +
- t0 * t3 * (ref[2][1] - ref[3][1]);
- x7 = t1 * t2 * (ref[0][0] - ref[1][0]) +
- t0 * t3 * (ref[3][0] - ref[2][0]);
- x8 = t1 * t2 * (ref[0][1] * ref[1][0] - ref[0][0] * ref[1][1]) +
- t0 * t3 * (ref[2][0] * ref[3][1] - ref[2][1] * ref[3][0]);
- break;
- default:
- av_assert0(0);
- }
-
- for (y = 0; y < h; y++){
- for (x = 0; x < w; x++){
- int u, v;
-
- u = lrint(SUB_PIXELS * (x0 * x + x1 * y + x2) /
- (x6 * x + x7 * y + x8));
- v = lrint(SUB_PIXELS * (x3 * x + x4 * y + x5) /
- (x6 * x + x7 * y + x8));
-
- s->pv[x + y * w][0] = u;
- s->pv[x + y * w][1] = v;
- }
- }
-
- return 0;
+ return perspective_resample_config_props(s->r, w, h, pix_fmt, ref);
}
static int config_input(AVFilterLink *inlink)
{
- AVFilterContext *ctx = inlink->dst;
- PerspectiveContext *s = ctx->priv;
- const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(inlink->format);
- int h = inlink->h;
- int w = inlink->w;
- int i, j, ret;
- s->hsub = desc->log2_chroma_w;
- s->vsub = desc->log2_chroma_h;
- s->nb_planes = av_pix_fmt_count_planes(inlink->format);
- if ((ret = av_image_fill_linesizes(s->linesize, inlink->format,
inlink->w)) < 0)
- return ret;
-
- s->height[1] = s->height[2] = AV_CEIL_RSHIFT(inlink->h,
desc->log2_chroma_h);
- s->height[0] = s->height[3] = inlink->h;
-
- s->pv = av_realloc_f(s->pv, w * h, 2 * sizeof(*s->pv));
- if (!s->pv)
- return AVERROR(ENOMEM);
-
- if (s->eval_mode == EVAL_MODE_INIT) {
- if ((ret = calc_persp_luts(ctx, inlink)) < 0) {
- return ret;
- }
- }
-
- for (i = 0; i < SUB_PIXELS; i++){
- double d = i / (double)SUB_PIXELS;
- double temp[4];
- double sum = 0;
-
- for (j = 0; j < 4; j++)
- temp[j] = get_coeff(j - d - 1);
-
- for (j = 0; j < 4; j++)
- sum += temp[j];
-
- for (j = 0; j < 4; j++)
- s->coeff[i][j] = lrint((1 << COEFF_BITS) * temp[j] / sum);
- }
-
- return 0;
-}
-
-typedef struct ThreadData {
- uint8_t *dst;
- int dst_linesize;
- uint8_t *src;
- int src_linesize;
- int w, h;
- int hsub, vsub;
-} ThreadData;
-
-static int resample_cubic(AVFilterContext *ctx, void *arg,
- int job, int nb_jobs)
-{
- PerspectiveContext *s = ctx->priv;
- ThreadData *td = arg;
- uint8_t *dst = td->dst;
- int dst_linesize = td->dst_linesize;
- uint8_t *src = td->src;
- int src_linesize = td->src_linesize;
- int w = td->w;
- int h = td->h;
- int hsub = td->hsub;
- int vsub = td->vsub;
- int start = (h * job) / nb_jobs;
- int end = (h * (job+1)) / nb_jobs;
- const int linesize = s->linesize[0];
- int x, y;
-
- for (y = start; y < end; y++) {
- int sy = y << vsub;
- for (x = 0; x < w; x++) {
- int u, v, subU, subV, sum, sx;
-
- sx = x << hsub;
- u = s->pv[sx + sy * linesize][0] >> hsub;
- v = s->pv[sx + sy * linesize][1] >> vsub;
- subU = u & (SUB_PIXELS - 1);
- subV = v & (SUB_PIXELS - 1);
- u >>= SUB_PIXEL_BITS;
- v >>= SUB_PIXEL_BITS;
-
- if (u > 0 && v > 0 && u < w - 2 && v < h - 2){
- const int index = u + v*src_linesize;
- const int a = s->coeff[subU][0];
- const int b = s->coeff[subU][1];
- const int c = s->coeff[subU][2];
- const int d = s->coeff[subU][3];
-
- sum = s->coeff[subV][0] * (a * src[index - 1 -
src_linesize] + b * src[index - 0 - src_linesize] +
- c * src[index + 1 -
src_linesize] + d * src[index + 2 - src_linesize]) +
- s->coeff[subV][1] * (a * src[index - 1
] + b * src[index - 0 ] +
- c * src[index + 1
] + d * src[index + 2 ]) +
- s->coeff[subV][2] * (a * src[index - 1 +
src_linesize] + b * src[index - 0 + src_linesize] +
- c * src[index + 1 +
src_linesize] + d * src[index + 2 + src_linesize]) +
- s->coeff[subV][3] * (a * src[index - 1 + 2 *
src_linesize] + b * src[index - 0 + 2 * src_linesize] +
- c * src[index + 1 + 2 *
src_linesize] + d * src[index + 2 + 2 * src_linesize]);
- } else {
- int dx, dy;
-
- sum = 0;
-
- for (dy = 0; dy < 4; dy++) {
- int iy = v + dy - 1;
-
- if (iy < 0)
- iy = 0;
- else if (iy >= h)
- iy = h-1;
- for (dx = 0; dx < 4; dx++) {
- int ix = u + dx - 1;
-
- if (ix < 0)
- ix = 0;
- else if (ix >= w)
- ix = w - 1;
-
- sum += s->coeff[subU][dx] * s->coeff[subV][dy] * src[
ix + iy * src_linesize];
- }
- }
- }
-
- sum = (sum + (1<<(COEFF_BITS * 2 - 1))) >> (COEFF_BITS * 2);
- sum = av_clip_uint8(sum);
- dst[x + y * dst_linesize] = sum;
- }
- }
- return 0;
-}
-
-static int resample_linear(AVFilterContext *ctx, void *arg,
- int job, int nb_jobs)
-{
- PerspectiveContext *s = ctx->priv;
- ThreadData *td = arg;
- uint8_t *dst = td->dst;
- int dst_linesize = td->dst_linesize;
- uint8_t *src = td->src;
- int src_linesize = td->src_linesize;
- int w = td->w;
- int h = td->h;
- int hsub = td->hsub;
- int vsub = td->vsub;
- int start = (h * job) / nb_jobs;
- int end = (h * (job+1)) / nb_jobs;
- const int linesize = s->linesize[0];
- int x, y;
-
- for (y = start; y < end; y++){
- int sy = y << vsub;
- for (x = 0; x < w; x++){
- int u, v, subU, subV, sum, sx, index, subUI, subVI;
-
- sx = x << hsub;
- u = s->pv[sx + sy * linesize][0] >> hsub;
- v = s->pv[sx + sy * linesize][1] >> vsub;
- subU = u & (SUB_PIXELS - 1);
- subV = v & (SUB_PIXELS - 1);
- u >>= SUB_PIXEL_BITS;
- v >>= SUB_PIXEL_BITS;
-
- index = u + v * src_linesize;
- subUI = SUB_PIXELS - subU;
- subVI = SUB_PIXELS - subV;
-
- if ((unsigned)u < (unsigned)(w - 1)){
- if((unsigned)v < (unsigned)(h - 1)){
- sum = subVI * (subUI * src[index] + subU * src[index + 1])
+
- subV * (subUI * src[index + src_linesize] + subU *
src[index + src_linesize + 1]);
- sum = (sum + (1 << (SUB_PIXEL_BITS * 2 - 1)))>>
(SUB_PIXEL_BITS * 2);
- } else {
- if (v < 0)
- v = 0;
- else
- v = h - 1;
- index = u + v * src_linesize;
- sum = subUI * src[index] + subU * src[index + 1];
- sum = (sum + (1 << (SUB_PIXEL_BITS - 1))) >>
SUB_PIXEL_BITS;
- }
- } else {
- if (u < 0)
- u = 0;
- else
- u = w - 1;
- if ((unsigned)v < (unsigned)(h - 1)){
- index = u + v * src_linesize;
- sum = subVI * src[index] + subV * src[index +
src_linesize];
- sum = (sum + (1 << (SUB_PIXEL_BITS - 1))) >>
SUB_PIXEL_BITS;
- } else {
- if (v < 0)
- v = 0;
- else
- v = h - 1;
- index = u + v * src_linesize;
- sum = src[index];
- }
- }
-
- sum = av_clip_uint8(sum);
- dst[x + y * dst_linesize] = sum;
- }
- }
- return 0;
+ return config_props(inlink->dst, inlink->w, inlink->h, inlink->format);
}
static av_cold int init(AVFilterContext *ctx)
{
PerspectiveContext *s = ctx->priv;
- switch (s->interpolation) {
- case LINEAR: s->perspective = resample_linear; break;
- case CUBIC: s->perspective = resample_cubic; break;
- }
+ s->r = perspective_resample_context_alloc(s->interpolation, s->sense);
+ if (!s->r)
+ return AVERROR(ENOMEM);
return 0;
}
@@ -445,7 +137,6 @@ static int filter_frame(AVFilterLink *inlink, AVFrame
*frame)
AVFilterLink *outlink = ctx->outputs[0];
PerspectiveContext *s = ctx->priv;
AVFrame *out;
- int plane;
int ret;
out = ff_get_video_buffer(outlink, outlink->w, outlink->h);
@@ -456,26 +147,13 @@ static int filter_frame(AVFilterLink *inlink, AVFrame
*frame)
av_frame_copy_props(out, frame);
if (s->eval_mode == EVAL_MODE_FRAME) {
- if ((ret = calc_persp_luts(ctx, inlink)) < 0) {
+ if ((ret = config_props(ctx, frame->width, frame->height,
frame->format)) < 0) {
av_frame_free(&out);
return ret;
}
}
- for (plane = 0; plane < s->nb_planes; plane++) {
- int hsub = plane == 1 || plane == 2 ? s->hsub : 0;
- int vsub = plane == 1 || plane == 2 ? s->vsub : 0;
- ThreadData td = {.dst = out->data[plane],
- .dst_linesize = out->linesize[plane],
- .src = frame->data[plane],
- .src_linesize = frame->linesize[plane],
- .w = s->linesize[plane],
- .h = s->height[plane],
- .hsub = hsub,
- .vsub = vsub };
- ff_filter_execute(ctx, s->perspective, &td, NULL,
- FFMIN(td.h, ff_filter_get_nb_threads(ctx)));
- }
+ perspective_resample(s->r, ctx, frame, out);
av_frame_free(&frame);
return ff_filter_frame(outlink, out);
@@ -485,7 +163,7 @@ static av_cold void uninit(AVFilterContext *ctx)
{
PerspectiveContext *s = ctx->priv;
- av_freep(&s->pv);
+ perspective_resample_context_free(&s->r);
}
static const AVFilterPad perspective_inputs[] = {
--
2.39.1
_______________________________________________
ffmpeg-devel mailing list
ffmpeg-devel@ffmpeg.org
https://ffmpeg.org/mailman/listinfo/ffmpeg-devel
To unsubscribe, visit link above, or email
ffmpeg-devel-requ...@ffmpeg.org with subject "unsubscribe".
