[FFmpeg-devel] [PATCH] avfilter: add shear video filter
Paul B Mahol
onemda at gmail.com
Sat Jan 23 14:14:30 EET 2021
Signed-off-by: Paul B Mahol <onemda at gmail.com>
---
doc/filters.texi | 27 ++++
libavfilter/Makefile | 1 +
libavfilter/allfilters.c | 1 +
libavfilter/vf_shear.c | 309 +++++++++++++++++++++++++++++++++++++++
4 files changed, 338 insertions(+)
create mode 100644 libavfilter/vf_shear.c
diff --git a/doc/filters.texi b/doc/filters.texi
index 7cb0d868d0..c2d7bac51d 100644
--- a/doc/filters.texi
+++ b/doc/filters.texi
@@ -17808,6 +17808,33 @@ Keep the same colorspace property (default).
@end table
@end table
+ at section shear
+Apply shear transform to input video.
+
+This filter supports the following options:
+
+ at table @option
+ at item shx
+Shear factor in X-direction. Default value is 0.
+Allowed range is from -2 to 2.
+
+ at item shy
+Shear factor in Y-direction. Default value is 0.
+Allowed range is from -2 to 2.
+
+ at item fillcolor, c
+Set the color used to fill the output area not covered by the transformed
+video. For the general syntax of this option, check the
+ at ref{color syntax,,"Color" section in the ffmpeg-utils manual,ffmpeg-utils}.
+If the special value "none" is selected then no
+background is printed (useful for example if the background is never shown).
+
+Default value is "black".
+
+ at item interp
+Set interpolation type. Can be @code{bilinear} or @code{nearest}. Default is @code{bilinear}.
+ at end table
+
@section showinfo
Show a line containing various information for each input video frame.
diff --git a/libavfilter/Makefile b/libavfilter/Makefile
index fb7bc8f140..b930a00d8b 100644
--- a/libavfilter/Makefile
+++ b/libavfilter/Makefile
@@ -403,6 +403,7 @@ OBJS-$(CONFIG_SETRANGE_FILTER) += vf_setparams.o
OBJS-$(CONFIG_SETSAR_FILTER) += vf_aspect.o
OBJS-$(CONFIG_SETTB_FILTER) += settb.o
OBJS-$(CONFIG_SHARPNESS_VAAPI_FILTER) += vf_misc_vaapi.o vaapi_vpp.o
+OBJS-$(CONFIG_SHEAR_FILTER) += vf_shear.o
OBJS-$(CONFIG_SHOWINFO_FILTER) += vf_showinfo.o
OBJS-$(CONFIG_SHOWPALETTE_FILTER) += vf_showpalette.o
OBJS-$(CONFIG_SHUFFLEFRAMES_FILTER) += vf_shuffleframes.o
diff --git a/libavfilter/allfilters.c b/libavfilter/allfilters.c
index 139ba15f7c..616962690b 100644
--- a/libavfilter/allfilters.c
+++ b/libavfilter/allfilters.c
@@ -384,6 +384,7 @@ extern AVFilter ff_vf_setrange;
extern AVFilter ff_vf_setsar;
extern AVFilter ff_vf_settb;
extern AVFilter ff_vf_sharpness_vaapi;
+extern AVFilter ff_vf_shear;
extern AVFilter ff_vf_showinfo;
extern AVFilter ff_vf_showpalette;
extern AVFilter ff_vf_shuffleframes;
diff --git a/libavfilter/vf_shear.c b/libavfilter/vf_shear.c
new file mode 100644
index 0000000000..dd301b1a78
--- /dev/null
+++ b/libavfilter/vf_shear.c
@@ -0,0 +1,309 @@
+/*
+ * Copyright (c) 2021 Paul B Mahol
+ *
+ * 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 "libavutil/avstring.h"
+#include "libavutil/opt.h"
+#include "libavutil/intreadwrite.h"
+#include "libavutil/parseutils.h"
+#include "libavutil/pixdesc.h"
+
+#include "avfilter.h"
+#include "drawutils.h"
+#include "internal.h"
+#include "video.h"
+
+#include <float.h>
+
+typedef struct ShearContext {
+ const AVClass *class;
+
+ float shx, shy;
+ int interp;
+
+ uint8_t fillcolor[4]; ///< color expressed either in YUVA or RGBA colorspace for the padding area
+ char *fillcolor_str;
+ int fillcolor_enable;
+ int nb_planes;
+ int depth;
+ FFDrawContext draw;
+ FFDrawColor color;
+
+ int hsub, vsub;
+ int planewidth[4];
+ int planeheight[4];
+
+ int (*filter_slice[2])(AVFilterContext *ctx, void *arg, int jobnr, int nb_jobs);
+} ShearContext;
+
+typedef struct ThreadData {
+ AVFrame *in, *out;
+} ThreadData;
+
+#define OFFSET(x) offsetof(ShearContext, x)
+#define FLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM
+#define TFLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM|AV_OPT_FLAG_RUNTIME_PARAM
+
+static const AVOption shear_options[] = {
+ { "shx", "set x shear factor", OFFSET(shx), AV_OPT_TYPE_FLOAT, {.dbl=0.}, -2, 2, .flags=TFLAGS },
+ { "shy", "set y shear factor", OFFSET(shy), AV_OPT_TYPE_FLOAT, {.dbl=0.}, -2, 2, .flags=TFLAGS },
+ { "fillcolor", "set background fill color", OFFSET(fillcolor_str), AV_OPT_TYPE_STRING, {.str="black"}, 0, 0, .flags=FLAGS },
+ { "c", "set background fill color", OFFSET(fillcolor_str), AV_OPT_TYPE_STRING, {.str="black"}, 0, 0, .flags=FLAGS },
+ { "interp", "set interpolation", OFFSET(interp), AV_OPT_TYPE_INT, {.i64=1}, 0, 1, .flags=TFLAGS, "interp" },
+ { "nearest", "nearest neighbour", 0, AV_OPT_TYPE_CONST, {.i64=0}, 0, 0, .flags=TFLAGS, "interp" },
+ { "bilinear", "bilinear", 0, AV_OPT_TYPE_CONST, {.i64=1}, 0, 0, .flags=TFLAGS, "interp" },
+ { NULL }
+};
+
+AVFILTER_DEFINE_CLASS(shear);
+
+static av_cold int init(AVFilterContext *ctx)
+{
+ ShearContext *s = ctx->priv;
+
+ if (!strcmp(s->fillcolor_str, "none"))
+ s->fillcolor_enable = 0;
+ else if (av_parse_color(s->fillcolor, s->fillcolor_str, -1, ctx) >= 0)
+ s->fillcolor_enable = 1;
+ else
+ return AVERROR(EINVAL);
+ return 0;
+}
+
+static int query_formats(AVFilterContext *ctx)
+{
+ static const enum AVPixelFormat pix_fmts[] = {
+ AV_PIX_FMT_GRAY8, AV_PIX_FMT_GRAY9,
+ AV_PIX_FMT_GRAY10, AV_PIX_FMT_GRAY12, AV_PIX_FMT_GRAY14,
+ AV_PIX_FMT_GRAY16,
+ AV_PIX_FMT_YUV410P, AV_PIX_FMT_YUV411P,
+ AV_PIX_FMT_YUV420P, AV_PIX_FMT_YUV422P,
+ AV_PIX_FMT_YUV440P, AV_PIX_FMT_YUV444P,
+ AV_PIX_FMT_YUVJ420P, AV_PIX_FMT_YUVJ422P,
+ AV_PIX_FMT_YUVJ440P, AV_PIX_FMT_YUVJ444P,
+ AV_PIX_FMT_YUVJ411P,
+ AV_PIX_FMT_YUV420P9, AV_PIX_FMT_YUV422P9, AV_PIX_FMT_YUV444P9,
+ AV_PIX_FMT_YUV420P10, AV_PIX_FMT_YUV422P10, AV_PIX_FMT_YUV444P10,
+ AV_PIX_FMT_YUV440P10,
+ AV_PIX_FMT_YUV444P12, AV_PIX_FMT_YUV422P12, AV_PIX_FMT_YUV420P12,
+ AV_PIX_FMT_YUV440P12,
+ AV_PIX_FMT_YUV444P14, AV_PIX_FMT_YUV422P14, AV_PIX_FMT_YUV420P14,
+ AV_PIX_FMT_YUV420P16, AV_PIX_FMT_YUV422P16, AV_PIX_FMT_YUV444P16,
+ AV_PIX_FMT_GBRP, AV_PIX_FMT_GBRP9, AV_PIX_FMT_GBRP10,
+ AV_PIX_FMT_GBRP12, AV_PIX_FMT_GBRP14, AV_PIX_FMT_GBRP16,
+ AV_PIX_FMT_YUVA420P, AV_PIX_FMT_YUVA422P, AV_PIX_FMT_YUVA444P,
+ AV_PIX_FMT_YUVA444P9, AV_PIX_FMT_YUVA444P10, AV_PIX_FMT_YUVA444P12, AV_PIX_FMT_YUVA444P16,
+ AV_PIX_FMT_YUVA422P9, AV_PIX_FMT_YUVA422P10, AV_PIX_FMT_YUVA422P12, AV_PIX_FMT_YUVA422P16,
+ AV_PIX_FMT_YUVA420P9, AV_PIX_FMT_YUVA420P10, AV_PIX_FMT_YUVA420P16,
+ AV_PIX_FMT_GBRAP, AV_PIX_FMT_GBRAP10, AV_PIX_FMT_GBRAP12, AV_PIX_FMT_GBRAP16,
+ AV_PIX_FMT_NONE
+ };
+
+ AVFilterFormats *fmts_list = ff_make_format_list(pix_fmts);
+ if (!fmts_list)
+ return AVERROR(ENOMEM);
+ return ff_set_common_formats(ctx, fmts_list);
+}
+
+#define NN(type, name) \
+static int filter_slice_nn##name(AVFilterContext *ctx, void *arg, int jobnr, \
+ int nb_jobs) \
+{ \
+ ThreadData *td = arg; \
+ AVFrame *in = td->in; \
+ AVFrame *out = td->out; \
+ ShearContext *s = ctx->priv; \
+ const float shx = s->shx; \
+ const float shy = s->shy; \
+ \
+ for (int p = 0; p < s->nb_planes; p++) { \
+ const int hsub = (p == 1 || p == 2) ? s->hsub: 1; \
+ const int vsub = (p == 1 || p == 2) ? s->vsub: 1; \
+ const int width = s->planewidth[p]; \
+ const int height = s->planeheight[p]; \
+ const int wx = vsub * shx * height * 0.5f / hsub; \
+ const int wy = hsub * shy * width * 0.5f / vsub; \
+ const int slice_start = (height * jobnr) / nb_jobs; \
+ const int slice_end = (height * (jobnr+1)) / nb_jobs; \
+ const int src_linesize = in->linesize[p] / sizeof(type); \
+ const int dst_linesize = out->linesize[p] / sizeof(type); \
+ const type *src = (const type *)in->data[p]; \
+ type *dst = (type *)out->data[p] + slice_start * dst_linesize; \
+ \
+ for (int y = slice_start; y < slice_end; y++) { \
+ for (int x = 0; x < width; x++) { \
+ int sx = x + vsub * shx * y / hsub - wx; \
+ int sy = y + hsub * shy * x / vsub - wy; \
+ \
+ if (sx >= 0 && sx < width - 1 && \
+ sy >= 0 && sy < height - 1) { \
+ dst[x] = src[sy * src_linesize + sx]; \
+ } \
+ } \
+ \
+ dst += dst_linesize; \
+ } \
+ } \
+ \
+ return 0; \
+}
+
+NN(uint8_t, 8)
+NN(uint16_t, 16)
+
+#define BL(type, name) \
+static int filter_slice_bl##name(AVFilterContext *ctx, void *arg, int jobnr, \
+ int nb_jobs) \
+{ \
+ ThreadData *td = arg; \
+ AVFrame *in = td->in; \
+ AVFrame *out = td->out; \
+ ShearContext *s = ctx->priv; \
+ const int depth = s->depth; \
+ const float shx = s->shx; \
+ const float shy = s->shy; \
+ \
+ for (int p = 0; p < s->nb_planes; p++) { \
+ const int hsub = (p == 1 || p == 2) ? s->hsub: 1; \
+ const int vsub = (p == 1 || p == 2) ? s->vsub: 1; \
+ const int width = s->planewidth[p]; \
+ const int height = s->planeheight[p]; \
+ const float wx = vsub * shx * height * 0.5f / hsub; \
+ const float wy = hsub * shy * width * 0.5f / vsub; \
+ const int slice_start = (height * jobnr) / nb_jobs; \
+ const int slice_end = (height * (jobnr+1)) / nb_jobs; \
+ const int src_linesize = in->linesize[p] / sizeof(type); \
+ const int dst_linesize = out->linesize[p] / sizeof(type); \
+ const type *src = (const type *)in->data[p]; \
+ type *dst = (type *)out->data[p] + slice_start * dst_linesize; \
+ \
+ for (int y = slice_start; y < slice_end; y++) { \
+ for (int x = 0; x < width; x++) { \
+ const float sx = x + vsub * shx * y / hsub - wx; \
+ const float sy = y + hsub * shy * x / vsub - wy; \
+ \
+ if (sx >= 0 && sx < width - 1 && \
+ sy >= 0 && sy < height - 1) { \
+ float sum = 0.f; \
+ int ax = floorf(sx); \
+ int ay = floorf(sy); \
+ float du = sx - ax; \
+ float dv = sy - ay; \
+ int bx = FFMIN(ax + 1, width - 1); \
+ int by = FFMIN(ay + 1, height - 1); \
+ \
+ sum += (1.f - du) * (1.f - dv) * src[ay * src_linesize + ax];\
+ sum += ( du) * (1.f - dv) * src[ay * src_linesize + bx];\
+ sum += (1.f - du) * ( dv) * src[by * src_linesize + ax];\
+ sum += ( du) * ( dv) * src[by * src_linesize + bx];\
+ dst[x] = av_clip_uintp2_c(lrintf(sum), depth); \
+ } \
+ } \
+ \
+ dst += dst_linesize; \
+ } \
+ } \
+ \
+ return 0; \
+}
+
+BL(uint8_t, 8)
+BL(uint16_t, 16)
+
+static int filter_frame(AVFilterLink *inlink, AVFrame *in)
+{
+ AVFilterContext *ctx = inlink->dst;
+ ShearContext *s = ctx->priv;
+ AVFilterLink *outlink = ctx->outputs[0];
+ ThreadData td;
+ AVFrame *out;
+
+ out = ff_get_video_buffer(outlink, outlink->w, outlink->h);
+ if (!out) {
+ av_frame_free(&in);
+ return AVERROR(ENOMEM);
+ }
+ av_frame_copy_props(out, in);
+
+ /* fill background */
+ if (s->fillcolor_enable)
+ ff_fill_rectangle(&s->draw, &s->color, out->data, out->linesize,
+ 0, 0, outlink->w, outlink->h);
+
+ td.in = in, td.out = out;
+ ctx->internal->execute(ctx, s->filter_slice[s->interp], &td, NULL, FFMIN(s->planeheight[1], ff_filter_get_nb_threads(ctx)));
+
+ av_frame_free(&in);
+ return ff_filter_frame(outlink, out);
+}
+
+static int config_output(AVFilterLink *outlink)
+{
+ AVFilterContext *ctx = outlink->src;
+ ShearContext *s = ctx->priv;
+ const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(outlink->format);
+
+ s->nb_planes = av_pix_fmt_count_planes(outlink->format);
+ s->depth = desc->comp[0].depth;
+ s->hsub = 1 << desc->log2_chroma_w;
+ s->vsub = 1 << desc->log2_chroma_h;
+ s->planewidth[1] = s->planewidth[2] = AV_CEIL_RSHIFT(ctx->inputs[0]->w, desc->log2_chroma_w);
+ s->planewidth[0] = s->planewidth[3] = ctx->inputs[0]->w;
+ s->planeheight[1] = s->planeheight[2] = AV_CEIL_RSHIFT(ctx->inputs[0]->h, desc->log2_chroma_h);
+ s->planeheight[0] = s->planeheight[3] = ctx->inputs[0]->h;
+
+ ff_draw_init(&s->draw, outlink->format, 0);
+ ff_draw_color(&s->draw, &s->color, s->fillcolor);
+
+ s->filter_slice[0] = s->depth <= 8 ? filter_slice_nn8 : filter_slice_nn16;
+ s->filter_slice[1] = s->depth <= 8 ? filter_slice_bl8 : filter_slice_bl16;
+
+ return 0;
+}
+
+static const AVFilterPad inputs[] = {
+ {
+ .name = "default",
+ .type = AVMEDIA_TYPE_VIDEO,
+ .filter_frame = filter_frame,
+ },
+ { NULL }
+};
+
+static const AVFilterPad outputs[] = {
+ {
+ .name = "default",
+ .type = AVMEDIA_TYPE_VIDEO,
+ .config_props = config_output,
+ },
+ { NULL }
+};
+
+AVFilter ff_vf_shear = {
+ .name = "shear",
+ .description = NULL_IF_CONFIG_SMALL("Shear transform the input image."),
+ .priv_size = sizeof(ShearContext),
+ .init = init,
+ .query_formats = query_formats,
+ .inputs = inputs,
+ .outputs = outputs,
+ .priv_class = &shear_class,
+ .flags = AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC | AVFILTER_FLAG_SLICE_THREADS,
+ .process_command = ff_filter_process_command,
+};
--
2.17.1
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