avfilter/vf_guided: support single input

Support single input for guided filter by adding guidance mode.
If the guidance mode is off, single input is required. And
edge-preserving smoothing is conducted. If the mode is on, two
inputs are needed. The second input serves as the guidance. For
this mode, more tasks are supported, such as detail enhancement,
dehazing and so on.

Signed-off-by: Xuewei Meng <xwmeng96@gmail.com>
Reviewed-by: Steven Liu <lq@chinaffmpeg.org>

1 files changed, 111 insertions, 57 deletions

diff --git a/libavfilter/vf_guided.c b/libavfilter/vf_guided.c
index ea537e40c6..202a6a0586 100644
--- a/libavfilter/vf_guided.c
+++ b/libavfilter/vf_guided.c
@@ -22,6 +22,7 @@
 #include "libavutil/opt.h"
 #include "libavutil/pixdesc.h"
 #include "avfilter.h"
+#include "filters.h"
 #include "formats.h"
 #include "framesync.h"
 #include "internal.h"
@@ -33,6 +34,12 @@ enum FilterModes {
     NB_MODES,
 };
 
+enum GuidanceModes {
+    OFF,
+    ON,
+    NB_GUIDANCE_MODES,
+};
+
 typedef struct GuidedContext {
     const AVClass *class;
     FFFrameSync fs;
@@ -41,7 +48,7 @@ typedef struct GuidedContext {
     float eps;
     int mode;
     int sub;
-
+    int guidance;
     int planes;
 
     int width;
@@ -59,13 +66,16 @@ typedef struct GuidedContext {
 #define FLAGS AV_OPT_FLAG_VIDEO_PARAM|AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_RUNTIME_PARAM
 
 static const AVOption guided_options[] = {
-    { "radius", "set the box radius",                               OFFSET(radius), AV_OPT_TYPE_INT,   {.i64 = 3    },     1,           20, FLAGS },
-    { "eps",    "set the regularization parameter (with square)",   OFFSET(eps),    AV_OPT_TYPE_FLOAT, {.dbl = 0.01 },   0.0,            1, FLAGS },
-    { "mode",   "set filtering mode (0: basic mode; 1: fast mode)", OFFSET(mode),   AV_OPT_TYPE_INT,   {.i64 = BASIC}, BASIC, NB_MODES - 1, FLAGS, "mode" },
-    { "basic",  "basic guided filter",                              0,              AV_OPT_TYPE_CONST, {.i64 = BASIC},     0,            0, FLAGS, "mode" },
-    { "fast",   "fast guided filter",                               0,              AV_OPT_TYPE_CONST, {.i64 = FAST },     0,            0, FLAGS, "mode" },
-    { "sub",    "subsampling ratio for fast mode",                  OFFSET(sub),    AV_OPT_TYPE_INT,   {.i64 = 4    },     2,           64, FLAGS },
-    { "planes", "set planes to filter",                             OFFSET(planes), AV_OPT_TYPE_INT,   {.i64=1      },     0,          0xF, FLAGS },
+    { "radius",   "set the box radius",                               OFFSET(radius),   AV_OPT_TYPE_INT,   {.i64 = 3    },     1,                    20, FLAGS },
+    { "eps",      "set the regularization parameter (with square)",   OFFSET(eps),      AV_OPT_TYPE_FLOAT, {.dbl = 0.01 },   0.0,                     1, FLAGS },
+    { "mode",     "set filtering mode (0: basic mode; 1: fast mode)", OFFSET(mode),     AV_OPT_TYPE_INT,   {.i64 = BASIC}, BASIC,          NB_MODES - 1, FLAGS, "mode" },
+    { "basic",    "basic guided filter",                              0,                AV_OPT_TYPE_CONST, {.i64 = BASIC},     0,                     0, FLAGS, "mode" },
+    { "fast",     "fast guided filter",                               0,                AV_OPT_TYPE_CONST, {.i64 = FAST },     0,                     0, FLAGS, "mode" },
+    { "sub",      "subsampling ratio for fast mode",                  OFFSET(sub),      AV_OPT_TYPE_INT,   {.i64 = 4    },     2,                    64, FLAGS },
+    { "guidance", "set guidance mode (0: off mode; 1: on mode)",      OFFSET(guidance), AV_OPT_TYPE_INT,   {.i64 = OFF  },   OFF, NB_GUIDANCE_MODES - 1, FLAGS, "guidance" },
+    { "off",      "only one input is enabled",                        0,                AV_OPT_TYPE_CONST, {.i64 = OFF  },     0,                     0, FLAGS, "guidance" },
+    { "on",       "two inputs are required",                          0,                AV_OPT_TYPE_CONST, {.i64 = ON   },     0,                     0, FLAGS, "guidance" },
+    { "planes",   "set planes to filter",                             OFFSET(planes),   AV_OPT_TYPE_INT,   {.i64 = 1    },     0,                   0xF, FLAGS },
     { NULL }
 };
 
@@ -149,16 +159,6 @@ static int config_input(AVFilterLink *inlink)
     GuidedContext *s = ctx->priv;
     const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(inlink->format);
 
-    if (ctx->inputs[0]->w != ctx->inputs[1]->w ||
-        ctx->inputs[0]->h != ctx->inputs[1]->h) {
-        av_log(ctx, AV_LOG_ERROR, "Width and height of input videos must be same.\n");
-        return AVERROR(EINVAL);
-    }
-    if (ctx->inputs[0]->format != ctx->inputs[1]->format) {
-        av_log(ctx, AV_LOG_ERROR, "Inputs must be of same pixel format.\n");
-        return AVERROR(EINVAL);
-    }
-
     if (s->mode == BASIC) {
         s->sub = 1;
     }
@@ -230,7 +230,7 @@ static int guided_##name(AVFilterContext *ctx, GuidedContext *s,
     meanB  = av_calloc(w * h, sizeof(float));                                           \
                                                                                         \
     if (!I || !II || !P || !IP || !meanI || !meanII || !meanP ||                        \
-        !meanIP || !A || !B || !meanA || !meanB){                                       \
+        !meanIP || !A || !B || !meanA || !meanB) {                                      \
         ret = AVERROR(ENOMEM);                                                          \
         goto end;                                                                       \
     }                                                                                   \
@@ -304,47 +304,54 @@ end:
 GUIDED(uint8_t, byte)
 GUIDED(uint16_t, word)
 
-static int process_frame(FFFrameSync *fs)
+static int filter_frame(AVFilterContext *ctx, AVFrame **out, AVFrame *in, AVFrame *ref)
 {
-    AVFilterContext *ctx = fs->parent;
-    GuidedContext *s = fs->opaque;
+    GuidedContext *s = ctx->priv;
     AVFilterLink *outlink = ctx->outputs[0];
-    AVFrame *out_frame = NULL, *main_frame = NULL, *ref_frame = NULL;
-    int ret;
-
-    ret = ff_framesync_dualinput_get(fs, &main_frame, &ref_frame);
-    if (ret < 0)
-        return ret;
-
-    out_frame = ff_get_video_buffer(outlink, outlink->w, outlink->h);
-    if (!out_frame) {
-        av_frame_free(&main_frame);
+    *out = ff_get_video_buffer(outlink, outlink->w, outlink->h);
+    if (!*out)
         return AVERROR(ENOMEM);
-    }
-    av_frame_copy_props(out_frame, main_frame);
+    av_frame_copy_props(*out, in);
 
     for (int plane = 0; plane < s->nb_planes; plane++) {
         if (!(s->planes & (1 << plane))) {
-            av_image_copy_plane(out_frame->data[plane], out_frame->linesize[plane],
-                                main_frame->data[plane], main_frame->linesize[plane],
+            av_image_copy_plane((*out)->data[plane], (*out)->linesize[plane],
+                                in->data[plane], in->linesize[plane],
                                 s->planewidth[plane] * ((s->depth + 7) / 8), s->planeheight[plane]);
             continue;
         }
         if (s->depth <= 8)
-           guided_byte(ctx, s, main_frame->data[plane], ref_frame->data[plane], out_frame->data[plane], s->radius, s->eps,
+           guided_byte(ctx, s, in->data[plane], ref->data[plane], (*out)->data[plane], s->radius, s->eps,
                        s->planewidth[plane], s->planeheight[plane],
-                       main_frame->linesize[plane], ref_frame->linesize[plane], out_frame->linesize[plane], (1 << s->depth) - 1.f);
+                       in->linesize[plane], ref->linesize[plane], (*out)->linesize[plane], (1 << s->depth) - 1.f);
         else
-           guided_word(ctx, s, main_frame->data[plane], ref_frame->data[plane], out_frame->data[plane], s->radius, s->eps,
+           guided_word(ctx, s, in->data[plane], ref->data[plane], (*out)->data[plane], s->radius, s->eps,
                        s->planewidth[plane], s->planeheight[plane],
-                       main_frame->linesize[plane] / 2, ref_frame->linesize[plane] / 2, out_frame->linesize[plane] / 2, (1 << s->depth) - 1.f);
+                       in->linesize[plane] / 2, ref->linesize[plane] / 2, (*out)->linesize[plane] / 2, (1 << s->depth) - 1.f);
+    }
+
+    return 0;
+}
+
+static int process_frame(FFFrameSync *fs)
+{
+    AVFilterContext *ctx = fs->parent;
+    AVFilterLink *outlink = ctx->outputs[0];
+    AVFrame *out_frame = NULL, *main_frame = NULL, *ref_frame = NULL;
+    int ret;
+    ret = ff_framesync_dualinput_get(fs, &main_frame, &ref_frame);
+    if (ret < 0)
+        return ret;
+
+    ret = filter_frame(ctx, &out_frame, main_frame, ref_frame);
+    if (ret < 0) {
+        return ret;
     }
     av_frame_free(&main_frame);
 
     return ff_filter_frame(outlink, out_frame);
 }
 
-
 static int config_output(AVFilterLink *outlink)
 {
     AVFilterContext *ctx = outlink->src;
@@ -354,12 +361,27 @@ static int config_output(AVFilterLink *outlink)
     FFFrameSyncIn *in;
     int ret;
 
+    if (s->guidance == ON) {
+        if (ctx->inputs[0]->w != ctx->inputs[1]->w ||
+            ctx->inputs[0]->h != ctx->inputs[1]->h) {
+            av_log(ctx, AV_LOG_ERROR, "Width and height of input videos must be same.\n");
+            return AVERROR(EINVAL);
+        }
+        if (ctx->inputs[0]->format != ctx->inputs[1]->format) {
+            av_log(ctx, AV_LOG_ERROR, "Inputs must be of same pixel format.\n");
+            return AVERROR(EINVAL);
+        }
+    }
 
     outlink->w = mainlink->w;
     outlink->h = mainlink->h;
     outlink->time_base = mainlink->time_base;
     outlink->sample_aspect_ratio = mainlink->sample_aspect_ratio;
     outlink->frame_rate = mainlink->frame_rate;
+
+    if (s->guidance == OFF)
+        return 0;
+
     if ((ret = ff_framesync_init(&s->fs, ctx, 2)) < 0)
         return ret;
 
@@ -383,22 +405,66 @@ static int config_output(AVFilterLink *outlink)
 static int activate(AVFilterContext *ctx)
 {
     GuidedContext *s = ctx->priv;
-    return ff_framesync_activate(&s->fs);
+    AVFrame *frame = NULL;
+    AVFrame *out = NULL;
+    int ret, status;
+    int64_t pts;
+    if (s->guidance)
+        return ff_framesync_activate(&s->fs);
+
+    FF_FILTER_FORWARD_STATUS_BACK(ctx->outputs[0], ctx->inputs[0]);
+
+    if ((ret = ff_inlink_consume_frame(ctx->inputs[0], &frame)) > 0) {
+        ret = filter_frame(ctx, &out, frame, frame);
+        av_frame_free(&frame);
+        if (ret < 0)
+            return ret;
+        ret = ff_filter_frame(ctx->outputs[0], out);
+    }
+    if (ret < 0)
+        return ret;
+    if (ff_inlink_acknowledge_status(ctx->inputs[0], &status, &pts)) {
+        ff_outlink_set_status(ctx->outputs[0], status, pts);
+        return 0;
+    }
+    if (ff_outlink_frame_wanted(ctx->outputs[0]))
+        ff_inlink_request_frame(ctx->inputs[0]);
+    return 0;
 }
 
 static av_cold int init(AVFilterContext *ctx)
 {
+    GuidedContext *s = ctx->priv;
+    AVFilterPad pad = { 0 };
+    int ret;
+
+    pad.type         = AVMEDIA_TYPE_VIDEO;
+    pad.name         = "source";
+    pad.config_props = config_input;
+
+    if ((ret = ff_insert_inpad(ctx, 0, &pad)) < 0)
+        return ret;
+
+    if (s->guidance == ON) {
+        pad.type         = AVMEDIA_TYPE_VIDEO;
+        pad.name         = "guidance";
+        pad.config_props = NULL;
+
+        if ((ret = ff_insert_inpad(ctx, 1, &pad)) < 0)
+            return ret;
+    }
+
     return 0;
 }
 
 static av_cold void uninit(AVFilterContext *ctx)
 {
     GuidedContext *s = ctx->priv;
-    ff_framesync_uninit(&s->fs);
+    if (s->guidance == ON)
+        ff_framesync_uninit(&s->fs);
     return;
 }
 
-
 static int process_command(AVFilterContext *ctx,
                            const char *cmd,
                            const char *arg,
@@ -414,18 +480,6 @@ static int process_command(AVFilterContext *ctx,
     return 0;
 }
 
-static const AVFilterPad guided_inputs[] = {
-    {
-        .name         = "main",
-        .type         = AVMEDIA_TYPE_VIDEO,
-    },{
-        .name         = "reference",
-        .type         = AVMEDIA_TYPE_VIDEO,
-        .config_props = config_input,
-    },
-    { NULL }
-};
-
 static const AVFilterPad guided_outputs[] = {
     {
         .name = "default",
@@ -444,7 +498,7 @@ const AVFilter ff_vf_guided = {
     .priv_size       = sizeof(GuidedContext),
     .priv_class      = &guided_class,
     .activate        = activate,
-    .inputs          = guided_inputs,
+    .inputs          = NULL,
     .outputs         = guided_outputs,
     .flags           = AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC | AVFILTER_FLAG_SLICE_THREADS,
     .process_command = process_command,