avfilter: add deband filter

Signed-off-by: Paul B Mahol <onemda@gmail.com>

Changelog

@@ -20,6 +20,7 @@ version <next>:
 - Dynamic Audio Normalizer as dynaudnorm filter
 - Reverse filter
 - Random filter
+- deband filter
 
 
 version 2.7:

doc/filters.texi

@@ -3878,6 +3878,43 @@ Violent denoise using a block size of @code{16x16}:
 dctdnoiz=15:n=4
 @end example
 
+@section deband
+
+Remove banding artifacts from input video.
+It works by replacing banded pixels with average value of referenced pixels.
+
+The filter accepts the following options:
+
+@table @option
+@item 1thr
+@item 2thr
+@item 3thr
+@item 4thr
+Set banding detection threshold for each plane. Default is 0.02.
+Valid range is 0.00003 to 0.5.
+If difference between current pixel and reference pixel is less than threshold,
+it will be considered as banded.
+
+@item range, r
+Banding detection range in pixels. Default is 16. If positive, random number
+in range 0 to set value will be used. If negative, exact absolute value
+will be used.
+The range defines square of four pixels around current pixel.
+
+@item direction, d
+Set direction in radians from which four pixel will be compared. If positive,
+random direction from 0 to set direction will be picked. If negative, exact of
+absolute value will be picked. For example direction 0, -PI or -2*PI radians
+will pick only pixels on same row and -PI/2 will pick only pixels on same
+column.
+
+@item blur
+If enabled, current pixel is compared with average value of all four
+surrounding pixels. The default is enabled. If disabled current pixel is
+compared with all four surrounding pixels. The pixel is considered banded
+if only all four differences with surrounding pixels are less than threshold.
+@end table
+
 @anchor{decimate}
 @section decimate
 

libavfilter/Makefile

@@ -112,6 +112,7 @@ OBJS-$(CONFIG_CROP_FILTER)                   += vf_crop.o
 OBJS-$(CONFIG_CROPDETECT_FILTER)             += vf_cropdetect.o
 OBJS-$(CONFIG_CURVES_FILTER)                 += vf_curves.o
 OBJS-$(CONFIG_DCTDNOIZ_FILTER)               += vf_dctdnoiz.o
+OBJS-$(CONFIG_DEBAND_FILTER)                 += vf_deband.o
 OBJS-$(CONFIG_DECIMATE_FILTER)               += vf_decimate.o
 OBJS-$(CONFIG_DEFLATE_FILTER)                += vf_neighbor.o
 OBJS-$(CONFIG_DEJUDDER_FILTER)               += vf_dejudder.o

libavfilter/allfilters.c

@@ -128,6 +128,7 @@ void avfilter_register_all(void)
     REGISTER_FILTER(CROPDETECT,     cropdetect,     vf);
     REGISTER_FILTER(CURVES,         curves,         vf);
     REGISTER_FILTER(DCTDNOIZ,       dctdnoiz,       vf);
+    REGISTER_FILTER(DEBAND,         deband,         vf);
     REGISTER_FILTER(DECIMATE,       decimate,       vf);
     REGISTER_FILTER(DEFLATE,        deflate,        vf);
     REGISTER_FILTER(DEJUDDER,       dejudder,       vf);

libavfilter/version.h

@@ -30,7 +30,7 @@
 #include "libavutil/version.h"
 
 #define LIBAVFILTER_VERSION_MAJOR  5
-#define LIBAVFILTER_VERSION_MINOR  25
+#define LIBAVFILTER_VERSION_MINOR  27
 #define LIBAVFILTER_VERSION_MICRO 100
 
 #define LIBAVFILTER_VERSION_INT AV_VERSION_INT(LIBAVFILTER_VERSION_MAJOR, \

libavfilter/vf_deband.c

+/*
+ * Copyright (c) 2015 Niklas Haas
+ * Copyright (c) 2015 Paul B Mahol
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+#include "libavutil/opt.h"
+#include "libavutil/pixdesc.h"
+#include "avfilter.h"
+#include "internal.h"
+#include "video.h"
+
+typedef struct DebandContext {
+    const AVClass *class;
+
+    float threshold[4];
+    int range;
+    int blur;
+    float direction;
+
+    int nb_components;
+    int planewidth[4];
+    int planeheight[4];
+    int thr[4];
+
+    int *x_pos;
+    int *y_pos;
+
+    int (*deband)(AVFilterContext *ctx, void *arg, int jobnr, int nb_jobs);
+} DebandContext;
+
+#define OFFSET(x) offsetof(DebandContext, x)
+#define FLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM
+
+static const AVOption deband_options[] = {
+    { "1thr",      "set 1st plane threshold", OFFSET(threshold[0]), AV_OPT_TYPE_FLOAT, {.dbl=0.02},  0.00003,     0.5, FLAGS },
+    { "2thr",      "set 2nd plane threshold", OFFSET(threshold[1]), AV_OPT_TYPE_FLOAT, {.dbl=0.02},  0.00003,     0.5, FLAGS },
+    { "3thr",      "set 3rd plane threshold", OFFSET(threshold[2]), AV_OPT_TYPE_FLOAT, {.dbl=0.02},  0.00003,     0.5, FLAGS },
+    { "4thr",      "set 4th plane threshold", OFFSET(threshold[3]), AV_OPT_TYPE_FLOAT, {.dbl=0.02},  0.00003,     0.5, FLAGS },
+    { "range",     "set range",               OFFSET(range),        AV_OPT_TYPE_INT,   {.i64=16},    INT_MIN, INT_MAX, FLAGS },
+    { "r",         "set range",               OFFSET(range),        AV_OPT_TYPE_INT,   {.i64=16},    INT_MIN, INT_MAX, FLAGS },
+    { "direction", "set direction",           OFFSET(direction),    AV_OPT_TYPE_FLOAT, {.dbl=2*M_PI},-2*M_PI,  2*M_PI, FLAGS },
+    { "d",         "set direction",           OFFSET(direction),    AV_OPT_TYPE_FLOAT, {.dbl=2*M_PI},-2*M_PI,  2*M_PI, FLAGS },
+    { "blur",      "enable blur",             OFFSET(blur),         AV_OPT_TYPE_INT,   {.i64=1},           0,       1, FLAGS },
+    { NULL }
+};
+
+AVFILTER_DEFINE_CLASS(deband);
+
+static int query_formats(AVFilterContext *ctx)
+{
+    static const enum AVPixelFormat pix_fmts[] = {
+        AV_PIX_FMT_GRAY8, AV_PIX_FMT_GRAY16,
+        AV_PIX_FMT_YUV444P,  AV_PIX_FMT_YUV422P,  AV_PIX_FMT_YUV420P,
+        AV_PIX_FMT_YUV411P,  AV_PIX_FMT_YUV410P,  AV_PIX_FMT_YUV440P,
+        AV_PIX_FMT_YUVJ444P, AV_PIX_FMT_YUVJ422P, AV_PIX_FMT_YUVJ420P,
+        AV_PIX_FMT_YUVJ411P, AV_PIX_FMT_YUVJ440P,
+        AV_PIX_FMT_YUVA420P, AV_PIX_FMT_YUVA422P, AV_PIX_FMT_YUVA444P,
+        AV_PIX_FMT_YUV420P9, AV_PIX_FMT_YUV422P9, AV_PIX_FMT_YUV444P9,
+        AV_PIX_FMT_YUVA420P9, AV_PIX_FMT_YUVA422P9, AV_PIX_FMT_YUVA444P9,
+        AV_PIX_FMT_YUVA420P10, AV_PIX_FMT_YUVA422P10, AV_PIX_FMT_YUVA444P10,
+        AV_PIX_FMT_YUV420P12, AV_PIX_FMT_YUV422P12, AV_PIX_FMT_YUV444P12,
+        AV_PIX_FMT_YUV420P14, AV_PIX_FMT_YUV422P14, AV_PIX_FMT_YUV444P14,
+        AV_PIX_FMT_GBRP, AV_PIX_FMT_GBRAP,
+        AV_PIX_FMT_GBRP9, AV_PIX_FMT_GBRP10,
+        AV_PIX_FMT_GBRP12, AV_PIX_FMT_GBRP14,
+        AV_PIX_FMT_GBRP16, AV_PIX_FMT_GBRAP16,
+        AV_PIX_FMT_YUV420P16, AV_PIX_FMT_YUV422P16, AV_PIX_FMT_YUV444P16,
+        AV_PIX_FMT_YUVA420P16, AV_PIX_FMT_YUVA422P16, AV_PIX_FMT_YUVA444P16,
+        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);
+}
+
+static float frand(int x, int y)
+{
+    const float r = sinf(x * 12.9898 + y * 78.233) * 43758.545;
+
+    return r - floorf(r);
+}
+
+static int inline get_avg(int ref0, int ref1, int ref2, int ref3)
+{
+    return (ref0 + ref1 + ref2 + ref3) / 4;
+}
+
+typedef struct ThreadData {
+    AVFrame *in, *out;
+} ThreadData;
+
+static int deband_8_c(AVFilterContext *ctx, void *arg, int jobnr, int nb_jobs)
+{
+    DebandContext *s = ctx->priv;
+    ThreadData *td = arg;
+    AVFrame *in = td->in;
+    AVFrame *out = td->out;
+    int x, y, p;
+
+    for (p = 0; p < s->nb_components; p++) {
+        const uint8_t *src_ptr = (const uint8_t *)in->data[p];
+        uint8_t *dst_ptr = (uint8_t *)out->data[p];
+        const int dst_linesize = out->linesize[p];
+        const int src_linesize = in->linesize[p];
+        const int thr = s->thr[p];
+        const int start = (s->planeheight[p] *  jobnr   ) / nb_jobs;
+        const int end   = (s->planeheight[p] * (jobnr+1)) / nb_jobs;
+        const int w = s->planewidth[p] - 1;
+        const int h = s->planeheight[p] - 1;
+
+        for (y = start; y < end; y++) {
+            const int pos = y * s->planeheight[0];
+
+            for (x = 0; x < s->planewidth[p]; x++) {
+                const int x_pos = s->x_pos[pos + x];
+                const int y_pos = s->y_pos[pos + x];
+                const int ref0 = src_ptr[av_clip(y +  y_pos, 0, h) * src_linesize + av_clip(x +  x_pos, 0, w)];
+                const int ref1 = src_ptr[av_clip(y + -y_pos, 0, h) * src_linesize + av_clip(x +  x_pos, 0, w)];
+                const int ref2 = src_ptr[av_clip(y + -y_pos, 0, h) * src_linesize + av_clip(x + -x_pos, 0, w)];
+                const int ref3 = src_ptr[av_clip(y +  y_pos, 0, h) * src_linesize + av_clip(x + -x_pos, 0, w)];
+                const int src0 = src_ptr[y * src_linesize + x];
+
+                if (s->blur) {
+                    const int avg = get_avg(ref0, ref1, ref2, ref3);
+                    const int diff = FFABS(src0 - avg);
+
+                    dst_ptr[y * dst_linesize + x] = diff < thr ? avg : src0;
+                } else {
+                    dst_ptr[y * dst_linesize + x] = (FFABS(src0 - ref0) < thr) &&
+                                                    (FFABS(src0 - ref1) < thr) &&
+                                                    (FFABS(src0 - ref2) < thr) &&
+                                                    (FFABS(src0 - ref3) < thr) ? get_avg(ref0, ref1, ref2, ref3) : src0;
+                }
+            }
+        }
+    }
+
+    return 0;
+}
+
+static int deband_16_c(AVFilterContext *ctx, void *arg, int jobnr, int nb_jobs)
+{
+    DebandContext *s = ctx->priv;
+    ThreadData *td = arg;
+    AVFrame *in = td->in;
+    AVFrame *out = td->out;
+    int x, y, p;
+
+    for (p = 0; p < s->nb_components; p++) {
+        const uint16_t *src_ptr = (const uint16_t *)in->data[p];
+        uint16_t *dst_ptr = (uint16_t *)out->data[p];
+        const int dst_linesize = out->linesize[p] / 2;
+        const int src_linesize = in->linesize[p] / 2;
+        const int thr = s->thr[p];
+        const int start = (s->planeheight[p] *  jobnr   ) / nb_jobs;
+        const int end   = (s->planeheight[p] * (jobnr+1)) / nb_jobs;
+        const int w = s->planewidth[p] - 1;
+        const int h = s->planeheight[p] - 1;
+
+        for (y = start; y < end; y++) {
+            const int pos = y * s->planeheight[0];
+
+            for (x = 0; x < s->planewidth[p]; x++) {
+                const int x_pos = s->x_pos[pos + x];
+                const int y_pos = s->y_pos[pos + x];
+                const int ref0 = src_ptr[av_clip(y +  y_pos, 0, h) * src_linesize + av_clip(x +  x_pos, 0, w)];
+                const int ref1 = src_ptr[av_clip(y + -y_pos, 0, h) * src_linesize + av_clip(x +  x_pos, 0, w)];
+                const int ref2 = src_ptr[av_clip(y + -y_pos, 0, h) * src_linesize + av_clip(x + -x_pos, 0, w)];
+                const int ref3 = src_ptr[av_clip(y +  y_pos, 0, h) * src_linesize + av_clip(x + -x_pos, 0, w)];
+                const int src0 = src_ptr[y * src_linesize + x];
+
+                if (s->blur) {
+                    const int avg = get_avg(ref0, ref1, ref2, ref3);
+                    const int diff = FFABS(src0 - avg);
+
+                    dst_ptr[y * dst_linesize + x] = diff < thr ? avg : src0;
+                } else {
+                    dst_ptr[y * dst_linesize + x] = (FFABS(src0 - ref0) < thr) &&
+                                                    (FFABS(src0 - ref1) < thr) &&
+                                                    (FFABS(src0 - ref2) < thr) &&
+                                                    (FFABS(src0 - ref3) < thr) ? get_avg(ref0, ref1, ref2, ref3) : src0;
+                }
+            }
+        }
+    }
+
+    return 0;
+}
+
+static int config_input(AVFilterLink *inlink)
+{
+    const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(inlink->format);
+    AVFilterContext *ctx = inlink->dst;
+    DebandContext *s = ctx->priv;
+    const float direction = s->direction;
+    const int range = s->range;
+    int x, y;
+
+    s->nb_components = desc->nb_components;
+
+    s->planeheight[1] = s->planeheight[2] = FF_CEIL_RSHIFT(inlink->h, desc->log2_chroma_h);
+    s->planeheight[0] = s->planeheight[3] = inlink->h;
+    s->planewidth[1]  = s->planewidth[2]  = FF_CEIL_RSHIFT(inlink->w, desc->log2_chroma_w);
+    s->planewidth[0]  = s->planewidth[3]  = inlink->w;
+
+    s->deband = desc->comp[0].depth_minus1 > 7 ? deband_16_c : deband_8_c;
+
+    s->thr[0] = ((1 << (desc->comp[0].depth_minus1 + 1)) - 1) * s->threshold[0];
+    s->thr[1] = ((1 << (desc->comp[1].depth_minus1 + 1)) - 1) * s->threshold[1];
+    s->thr[2] = ((1 << (desc->comp[2].depth_minus1 + 1)) - 1) * s->threshold[2];
+    s->thr[3] = ((1 << (desc->comp[3].depth_minus1 + 1)) - 1) * s->threshold[3];
+
+    s->x_pos = av_malloc(s->planewidth[0] * s->planeheight[0] * sizeof(*s->x_pos));
+    s->y_pos = av_malloc(s->planewidth[0] * s->planeheight[0] * sizeof(*s->y_pos));
+    if (!s->x_pos || !s->y_pos)
+        return AVERROR(ENOMEM);
+
+    for (y = 0; y < s->planeheight[0]; y++) {
+        for (x = 0; x < s->planewidth[0]; x++) {
+            const float r = frand(x, y);
+            const float dir = direction < 0 ? -direction : r * direction;
+            const int dist = range < 0 ? -range : r * range;
+
+            s->x_pos[y * s->planeheight[0] + x] = cosf(dir) * dist;
+            s->y_pos[y * s->planeheight[0] + x] = sinf(dir) * dist;
+        }
+    }
+
+    return 0;
+}
+
+static int filter_frame(AVFilterLink *inlink, AVFrame *in)
+{
+    AVFilterContext *ctx = inlink->dst;
+    AVFilterLink *outlink = ctx->outputs[0];
+    DebandContext *s = ctx->priv;
+    AVFrame *out;
+    ThreadData td;
+
+    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);
+
+    td.in = in; td.out = out;
+    ctx->internal->execute(ctx, s->deband, &td, NULL, FFMIN3(s->planeheight[1],
+                                                             s->planeheight[2],
+                                                             ctx->graph->nb_threads));
+
+    av_frame_free(&in);
+    return ff_filter_frame(outlink, out);
+}
+
+static av_cold void uninit(AVFilterContext *ctx)
+{
+    DebandContext *s = ctx->priv;
+
+    av_freep(&s->x_pos);
+    av_freep(&s->y_pos);
+}
+
+static const AVFilterPad avfilter_vf_deband_inputs[] = {
+    {
+        .name         = "default",
+        .type         = AVMEDIA_TYPE_VIDEO,
+        .config_props = config_input,
+        .filter_frame = filter_frame,
+    },
+    { NULL }
+};
+
+static const AVFilterPad avfilter_vf_deband_outputs[] = {
+    {
+        .name = "default",
+        .type = AVMEDIA_TYPE_VIDEO,
+    },
+    { NULL }
+};
+
+AVFilter ff_vf_deband = {
+    .name          = "deband",
+    .description   = NULL_IF_CONFIG_SMALL("Debands video."),
+    .priv_size     = sizeof(DebandContext),
+    .priv_class    = &deband_class,
+    .uninit        = uninit,
+    .query_formats = query_formats,
+    .inputs        = avfilter_vf_deband_inputs,
+    .outputs       = avfilter_vf_deband_outputs,
+    .flags         = AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC,
+};