avfilter: add lut2 filter

Changelog

@@ -20,6 +20,7 @@ version <next>:
 - fifo muxer
 - maskedclamp filter
 - hysteresis filter
+- lut2 filter
 
 
 version 3.1:

doc/filters.texi

@@ -9253,6 +9253,44 @@ lutyuv=u='(val-maxval/2)*2+maxval/2':v='(val-maxval/2)*2+maxval/2'
 @end example
 @end itemize
 
+@section lut2
+
+Compute and apply a lookup table from two video inputs.
+
+This filter accepts the following parameters:
+@table @option
+@item c0
+set first pixel component expression
+@item c1
+set second pixel component expression
+@item c2
+set third pixel component expression
+@item c3
+set fourth pixel component expression, corresponds to the alpha component
+@end table
+
+Each of them specifies the expression to use for computing the lookup table for
+the corresponding pixel component values.
+
+The exact component associated to each of the @var{c*} options depends on the
+format in inputs.
+
+The expressions can contain the following constants:
+
+@table @option
+@item w
+@item h
+The input width and height.
+
+@item x
+The first input value for the pixel component.
+
+@item y
+The second input value for the pixel component.
+@end table
+
+All expressions default to "x".
+
 @section maskedclamp
 
 Clamp the first input stream with the second input and third input stream.

libavfilter/Makefile

@@ -205,6 +205,7 @@ OBJS-$(CONFIG_KERNDEINT_FILTER)              += vf_kerndeint.o
 OBJS-$(CONFIG_LENSCORRECTION_FILTER)         += vf_lenscorrection.o
 OBJS-$(CONFIG_LOOP_FILTER)                   += f_loop.o
 OBJS-$(CONFIG_LUT_FILTER)                    += vf_lut.o
+OBJS-$(CONFIG_LUT2_FILTER)                   += vf_lut2.o framesync.o
 OBJS-$(CONFIG_LUT3D_FILTER)                  += vf_lut3d.o
 OBJS-$(CONFIG_LUTRGB_FILTER)                 += vf_lut.o
 OBJS-$(CONFIG_LUTYUV_FILTER)                 += vf_lut.o

libavfilter/allfilters.c

@@ -222,6 +222,7 @@ void avfilter_register_all(void)
     REGISTER_FILTER(LENSCORRECTION, lenscorrection, vf);
     REGISTER_FILTER(LOOP,           loop,           vf);
     REGISTER_FILTER(LUT,            lut,            vf);
+    REGISTER_FILTER(LUT2,           lut2,           vf);
     REGISTER_FILTER(LUT3D,          lut3d,          vf);
     REGISTER_FILTER(LUTRGB,         lutrgb,         vf);
     REGISTER_FILTER(LUTYUV,         lutyuv,         vf);

libavfilter/version.h

@@ -30,7 +30,7 @@
 #include "libavutil/version.h"
 
 #define LIBAVFILTER_VERSION_MAJOR   6
-#define LIBAVFILTER_VERSION_MINOR  54
+#define LIBAVFILTER_VERSION_MINOR  55
 #define LIBAVFILTER_VERSION_MICRO 100
 
 #define LIBAVFILTER_VERSION_INT AV_VERSION_INT(LIBAVFILTER_VERSION_MAJOR, \

libavfilter/vf_lut2.c

+/*
+ * Copyright (c) 2016 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/attributes.h"
+#include "libavutil/common.h"
+#include "libavutil/eval.h"
+#include "libavutil/opt.h"
+#include "libavutil/pixdesc.h"
+#include "avfilter.h"
+#include "drawutils.h"
+#include "formats.h"
+#include "internal.h"
+#include "video.h"
+#include "framesync.h"
+
+static const char *const var_names[] = {
+    "w",        ///< width of the input video
+    "h",        ///< height of the input video
+    "x",        ///< input value for the pixel from input #1
+    "y",        ///< input value for the pixel from input #2
+    NULL
+};
+
+enum var_name {
+    VAR_W,
+    VAR_H,
+    VAR_X,
+    VAR_Y,
+    VAR_VARS_NB
+};
+
+typedef struct LUT2Context {
+    const AVClass *class;
+
+    char   *comp_expr_str[4];
+
+    AVExpr *comp_expr[4];
+    double var_values[VAR_VARS_NB];
+    uint16_t *lut[4];  ///< lookup table for each component
+    int width[4], height[4];
+    int nb_planes;
+    int depth, depthx, depthy;
+
+    void (*lut2)(struct LUT2Context *s, AVFrame *dst, AVFrame *srcx, AVFrame *srcy);
+
+    FFFrameSync fs;
+} LUT2Context;
+
+#define OFFSET(x) offsetof(LUT2Context, x)
+#define FLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM
+
+static const AVOption lut2_options[] = {
+    { "c0", "set component #0 expression", OFFSET(comp_expr_str[0]),  AV_OPT_TYPE_STRING, { .str = "x" }, .flags = FLAGS },
+    { "c1", "set component #1 expression", OFFSET(comp_expr_str[1]),  AV_OPT_TYPE_STRING, { .str = "x" }, .flags = FLAGS },
+    { "c2", "set component #2 expression", OFFSET(comp_expr_str[2]),  AV_OPT_TYPE_STRING, { .str = "x" }, .flags = FLAGS },
+    { "c3", "set component #3 expression", OFFSET(comp_expr_str[3]),  AV_OPT_TYPE_STRING, { .str = "x" }, .flags = FLAGS },
+    { NULL }
+};
+
+static av_cold void uninit(AVFilterContext *ctx)
+{
+    LUT2Context *s = ctx->priv;
+    int i;
+
+    for (i = 0; i < 4; i++) {
+        av_expr_free(s->comp_expr[i]);
+        s->comp_expr[i] = NULL;
+        av_freep(&s->comp_expr_str[i]);
+        av_freep(&s->lut[i]);
+    }
+}
+
+static int query_formats(AVFilterContext *ctx)
+{
+    static const enum AVPixelFormat pix_fmts[] = {
+        AV_PIX_FMT_YUVA444P, AV_PIX_FMT_YUV444P, AV_PIX_FMT_YUV440P,
+        AV_PIX_FMT_YUVJ444P, AV_PIX_FMT_YUVJ440P,
+        AV_PIX_FMT_YUVA422P, AV_PIX_FMT_YUV422P, AV_PIX_FMT_YUVA420P, AV_PIX_FMT_YUV420P,
+        AV_PIX_FMT_YUVJ422P, AV_PIX_FMT_YUVJ420P,
+        AV_PIX_FMT_YUVJ411P, AV_PIX_FMT_YUV411P, AV_PIX_FMT_YUV410P,
+        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_YUV420P12, AV_PIX_FMT_YUV422P12, AV_PIX_FMT_YUV444P12, AV_PIX_FMT_YUV440P12,
+        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_GBRP, AV_PIX_FMT_GBRP9, AV_PIX_FMT_GBRP10,
+        AV_PIX_FMT_GBRP12,
+        AV_PIX_FMT_GBRAP, AV_PIX_FMT_GBRAP12,
+        AV_PIX_FMT_GRAY8,
+        AV_PIX_FMT_NONE
+    };
+
+    return ff_set_common_formats(ctx, ff_make_format_list(pix_fmts));
+}
+
+static int config_inputx(AVFilterLink *inlink)
+{
+    AVFilterContext *ctx = inlink->dst;
+    LUT2Context *s = ctx->priv;
+    const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(inlink->format);
+    int hsub = desc->log2_chroma_w;
+    int vsub = desc->log2_chroma_h;
+
+    s->nb_planes = av_pix_fmt_count_planes(inlink->format);
+    s->height[1] = s->height[2] = AV_CEIL_RSHIFT(inlink->h, vsub);
+    s->height[0] = s->height[3] = inlink->h;
+    s->width[1]  = s->width[2]  = AV_CEIL_RSHIFT(inlink->w, hsub);
+    s->width[0]  = s->width[3]  = inlink->w;
+
+    s->var_values[VAR_W] = inlink->w;
+    s->var_values[VAR_H] = inlink->h;
+    s->depthx = desc->comp[0].depth;
+
+    return 0;
+}
+
+static int config_inputy(AVFilterLink *inlink)
+{
+    AVFilterContext *ctx = inlink->dst;
+    LUT2Context *s = ctx->priv;
+    const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(inlink->format);
+
+    s->depthy = desc->comp[0].depth;
+
+    return 0;
+}
+
+static void lut2_8bit(struct LUT2Context *s, AVFrame *out, AVFrame *srcx, AVFrame *srcy)
+{
+    int p, y, x;
+
+    for (p = 0; p < s->nb_planes; p++) {
+        const uint16_t *lut = s->lut[p];
+        const uint8_t *srcxx, *srcyy;
+        uint8_t *dst;
+
+        dst   = out->data[p];
+        srcxx = srcx->data[p];
+        srcyy = srcy->data[p];
+
+        for (y = 0; y < s->height[p]; y++) {
+            for (x = 0; x < s->width[p]; x++) {
+                dst[x] = lut[(srcyy[x] << s->depthx) | srcxx[x]];
+            }
+
+            dst   += out->linesize[p];
+            srcxx += srcx->linesize[p];
+            srcyy += srcy->linesize[p];
+        }
+    }
+}
+
+static void lut2_16bit(struct LUT2Context *s, AVFrame *out, AVFrame *srcx, AVFrame *srcy)
+{
+    int p, y, x;
+
+    for (p = 0; p < s->nb_planes; p++) {
+        const uint16_t *lut = s->lut[p];
+        const uint16_t *srcxx, *srcyy;
+        uint16_t *dst;
+
+        dst   = (uint16_t *)out->data[p];
+        srcxx = (uint16_t *)srcx->data[p];
+        srcyy = (uint16_t *)srcy->data[p];
+
+        for (y = 0; y < s->height[p]; y++) {
+            for (x = 0; x < s->width[p]; x++) {
+                dst[x] = lut[(srcyy[x] << s->depthx) | srcxx[x]];
+            }
+
+            dst   += out->linesize[p]  / 2;
+            srcxx += srcx->linesize[p] / 2;
+            srcyy += srcy->linesize[p] / 2;
+        }
+    }
+}
+
+static int process_frame(FFFrameSync *fs)
+{
+    AVFilterContext *ctx = fs->parent;
+    LUT2Context *s = fs->opaque;
+    AVFilterLink *outlink = ctx->outputs[0];
+    AVFrame *out, *srcx, *srcy;
+    int ret;
+
+    if ((ret = ff_framesync_get_frame(&s->fs, 0, &srcx, 0)) < 0 ||
+        (ret = ff_framesync_get_frame(&s->fs, 1, &srcy, 0)) < 0)
+        return ret;
+
+    if (ctx->is_disabled) {
+        out = av_frame_clone(srcx);
+        if (!out)
+            return AVERROR(ENOMEM);
+    } else {
+        out = ff_get_video_buffer(outlink, outlink->w, outlink->h);
+        if (!out)
+            return AVERROR(ENOMEM);
+        av_frame_copy_props(out, srcx);
+
+        s->lut2(s, out, srcx, srcy);
+    }
+
+    out->pts = av_rescale_q(s->fs.pts, s->fs.time_base, outlink->time_base);
+
+    return ff_filter_frame(outlink, out);
+}
+
+static int config_output(AVFilterLink *outlink)
+{
+    AVFilterContext *ctx = outlink->src;
+    LUT2Context *s = ctx->priv;
+    AVFilterLink *srcx = ctx->inputs[0];
+    AVFilterLink *srcy = ctx->inputs[1];
+    FFFrameSyncIn *in;
+    int p, ret;
+
+    s->depth = s->depthx + s->depthy;
+
+    if (srcx->format != srcy->format) {
+        av_log(ctx, AV_LOG_ERROR, "inputs must be of same pixel format\n");
+        return AVERROR(EINVAL);
+    }
+    if (srcx->w                       != srcy->w ||
+        srcx->h                       != srcy->h ||
+        srcx->sample_aspect_ratio.num != srcy->sample_aspect_ratio.num ||
+        srcx->sample_aspect_ratio.den != srcy->sample_aspect_ratio.den) {
+        av_log(ctx, AV_LOG_ERROR, "First input link %s parameters "
+               "(size %dx%d, SAR %d:%d) do not match the corresponding "
+               "second input link %s parameters (%dx%d, SAR %d:%d)\n",
+               ctx->input_pads[0].name, srcx->w, srcx->h,
+               srcx->sample_aspect_ratio.num,
+               srcx->sample_aspect_ratio.den,
+               ctx->input_pads[1].name,
+               srcy->w, srcy->h,
+               srcy->sample_aspect_ratio.num,
+               srcy->sample_aspect_ratio.den);
+        return AVERROR(EINVAL);
+    }
+
+    outlink->w = srcx->w;
+    outlink->h = srcx->h;
+    outlink->time_base = srcx->time_base;
+    outlink->sample_aspect_ratio = srcx->sample_aspect_ratio;
+    outlink->frame_rate = srcx->frame_rate;
+
+    if ((ret = ff_framesync_init(&s->fs, ctx, 2)) < 0)
+        return ret;
+
+    in = s->fs.in;
+    in[0].time_base = srcx->time_base;
+    in[1].time_base = srcy->time_base;
+    in[0].sync   = 1;
+    in[0].before = EXT_STOP;
+    in[0].after  = EXT_INFINITY;
+    in[1].sync   = 1;
+    in[1].before = EXT_STOP;
+    in[1].after  = EXT_INFINITY;
+    s->fs.opaque   = s;
+    s->fs.on_event = process_frame;
+
+    s->lut2 = s->depth > 16 ? lut2_16bit : lut2_8bit;
+
+    for (p = 0; p < s->nb_planes; p++) {
+        s->lut[p] = av_malloc_array(1 << s->depth, sizeof(uint16_t));
+        if (!s->lut[p])
+            return AVERROR(ENOMEM);
+    }
+
+    for (p = 0; p < s->nb_planes; p++) {
+        double res;
+        int x, y;
+
+        /* create the parsed expression */
+        av_expr_free(s->comp_expr[p]);
+        s->comp_expr[p] = NULL;
+        ret = av_expr_parse(&s->comp_expr[p], s->comp_expr_str[p],
+                            var_names, NULL, NULL, NULL, NULL, 0, ctx);
+        if (ret < 0) {
+            av_log(ctx, AV_LOG_ERROR,
+                   "Error when parsing the expression '%s' for the component %d.\n",
+                   s->comp_expr_str[p], p);
+            return AVERROR(EINVAL);
+        }
+
+        /* compute the lut */
+        for (y = 0; y < (1 << s->depthx); y++) {
+            s->var_values[VAR_Y] = y;
+            for (x = 0; x < (1 << s->depthx); x++) {
+                s->var_values[VAR_X] = x;
+                res = av_expr_eval(s->comp_expr[p], s->var_values, s);
+                if (isnan(res)) {
+                    av_log(ctx, AV_LOG_ERROR,
+                           "Error when evaluating the expression '%s' for the values %d and %d for the component %d.\n",
+                           s->comp_expr_str[p], x, y, p);
+                    return AVERROR(EINVAL);
+                }
+
+                s->lut[p][(y << s->depthx) + x] = res;
+            }
+        }
+    }
+
+    return ff_framesync_configure(&s->fs);
+}
+
+static int filter_frame(AVFilterLink *inlink, AVFrame *buf)
+{
+    LUT2Context *s = inlink->dst->priv;
+    return ff_framesync_filter_frame(&s->fs, inlink, buf);
+}
+
+static int request_frame(AVFilterLink *outlink)
+{
+    LUT2Context *s = outlink->src->priv;
+    return ff_framesync_request_frame(&s->fs, outlink);
+}
+
+static const AVFilterPad inputs[] = {
+    {
+        .name         = "srcx",
+        .type         = AVMEDIA_TYPE_VIDEO,
+        .filter_frame = filter_frame,
+        .config_props = config_inputx,
+    },
+    {
+        .name         = "srcy",
+        .type         = AVMEDIA_TYPE_VIDEO,
+        .filter_frame = filter_frame,
+        .config_props = config_inputy,
+    },
+    { NULL }
+};
+
+static const AVFilterPad outputs[] = {
+    {
+        .name          = "default",
+        .type          = AVMEDIA_TYPE_VIDEO,
+        .config_props  = config_output,
+        .request_frame = request_frame,
+    },
+    { NULL }
+};
+
+AVFILTER_DEFINE_CLASS(lut2);
+
+AVFilter ff_vf_lut2 = {
+    .name          = "lut2",
+    .description   = NULL_IF_CONFIG_SMALL("Compute and apply a lookup table from two video inputs."),
+    .priv_size     = sizeof(LUT2Context),
+    .priv_class    = &lut2_class,
+    .uninit        = uninit,
+    .query_formats = query_formats,
+    .inputs        = inputs,
+    .outputs       = outputs,
+    .flags         = AVFILTER_FLAG_SUPPORT_TIMELINE_INTERNAL,
+};