[FFmpeg-devel] [PATCH] libavfilter: add vf_hue.c

Jérémy Tran tran.jeremy.av at gmail.com
Sat Aug 11 11:35:03 CEST 2012


This is a port of the MPlayer hue filter (libmpcodecs/vf_hue.c)

Signed-off-by: Jérémy Tran <tran.jeremy.av at gmail.com>
---
 doc/filters.texi         |  20 +++++
 libavfilter/Makefile     |   1 +
 libavfilter/allfilters.c |   1 +
 libavfilter/vf_hue.c     | 216 +++++++++++++++++++++++++++++++++++++++++++++++
 4 files changed, 238 insertions(+)
 create mode 100644 libavfilter/vf_hue.c

diff --git a/doc/filters.texi b/doc/filters.texi
index 18be723..71f6670 100644
--- a/doc/filters.texi
+++ b/doc/filters.texi
@@ -2187,6 +2187,26 @@ a float number which specifies chroma temporal strength, defaults to
 @var{luma_tmp}*@var{chroma_spatial}/@var{luma_spatial}
 @end table
 
+ at section hue
+
+Modify the hue and/or the saturation of the input.
+
+The filter supports the following syntaxes:
+ at example
+# hue = 100 ; saturation = 1
+ffmpeg -i in.avi -vf hue=100:1
+
+# same command but using named options
+ffmpeg -i in.avi -vf hue=h=100:s=1
+ at end example
+
+ at table @option
+ at item hue
+A float number that specifies the hue in the [-360;360] range, defaults to 0.0.
+ at item saturation
+A float number that specifies the saturation in the [0;2] range, defaults to 1.0.
+ at end table
+
 @section idet
 
 Interlaceing detect filter. This filter tries to detect if the input is
diff --git a/libavfilter/Makefile b/libavfilter/Makefile
index 727ab4e..66b5d52 100644
--- a/libavfilter/Makefile
+++ b/libavfilter/Makefile
@@ -98,6 +98,7 @@ OBJS-$(CONFIG_FREI0R_FILTER)                 += vf_frei0r.o
 OBJS-$(CONFIG_GRADFUN_FILTER)                += vf_gradfun.o
 OBJS-$(CONFIG_HFLIP_FILTER)                  += vf_hflip.o
 OBJS-$(CONFIG_HQDN3D_FILTER)                 += vf_hqdn3d.o
+OBJS-$(CONFIG_HUE_FILTER)                    += vf_hue.o
 OBJS-$(CONFIG_IDET_FILTER)                   += vf_idet.o
 OBJS-$(CONFIG_LUT_FILTER)                    += vf_lut.o
 OBJS-$(CONFIG_LUTRGB_FILTER)                 += vf_lut.o
diff --git a/libavfilter/allfilters.c b/libavfilter/allfilters.c
index 403383d..f097bcf 100644
--- a/libavfilter/allfilters.c
+++ b/libavfilter/allfilters.c
@@ -88,6 +88,7 @@ void avfilter_register_all(void)
     REGISTER_FILTER (GRADFUN,     gradfun,     vf);
     REGISTER_FILTER (HFLIP,       hflip,       vf);
     REGISTER_FILTER (HQDN3D,      hqdn3d,      vf);
+    REGISTER_FILTER (HUE,         hue,         vf);
     REGISTER_FILTER (IDET,        idet,        vf);
     REGISTER_FILTER (LUT,         lut,         vf);
     REGISTER_FILTER (LUTRGB,      lutrgb,      vf);
diff --git a/libavfilter/vf_hue.c b/libavfilter/vf_hue.c
new file mode 100644
index 0000000..4993ae6
--- /dev/null
+++ b/libavfilter/vf_hue.c
@@ -0,0 +1,216 @@
+/*
+ * Copyright (c) 2003 Michael Niedermayer
+ * Copyright (c) 2012 Jeremy Tran
+ *
+ * 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.
+ */
+
+/**
+ * @file
+ * Apply a hue/saturation filter to the input video
+ * Ported from MPlayer libmpcodecs/vf_hue.c
+ */
+
+#include "libavutil/common.h"
+#include "libavutil/imgutils.h"
+#include "libavutil/mem.h"
+#include "libavutil/opt.h"
+#include "libavutil/pixdesc.h"
+
+#include "avfilter.h"
+#include "formats.h"
+#include "internal.h"
+#include "video.h"
+
+typedef struct {
+    const AVClass *class;
+    float         h;
+    float         s;
+    int32_t       hsub;
+    int32_t       vsub;
+    int32_t       sin;
+    int32_t       cos;
+} HueContext;
+
+#define OFFSET(x) offsetof(HueContext, x)
+static const AVOption hue_options[] = {
+    { "h", NULL, OFFSET(h), AV_OPT_TYPE_FLOAT, { 0 }, -360, 360, AV_OPT_FLAG_VIDEO_PARAM },
+    { "s", NULL, OFFSET(s), AV_OPT_TYPE_FLOAT, { 1 }, 0, 2, AV_OPT_FLAG_VIDEO_PARAM },
+    { NULL }
+};
+
+AVFILTER_DEFINE_CLASS(hue);
+
+static av_cold int init(AVFilterContext *ctx, const char *args)
+{
+    HueContext *hue = ctx->priv;
+    char *colon, *equal;
+    float h = 0, s = 1;
+    int32_t ret;
+
+    hue->class = &hue_class;
+
+    // named options syntax
+    if (equal = strchr(args, '=')) {
+        av_opt_set_defaults(hue);
+        ret = av_set_options_string(hue, args, "=", ":");
+        if (ret < 0) {
+            av_log(ctx, AV_LOG_ERROR,
+                   "Error parsing the options string: %s\n", args);
+            av_opt_free(hue);
+            return ret;
+        }
+    // compatibility syntax
+    } else {
+        sscanf(args, "%f:%f", &h, &s);
+        hue->h = h;
+        hue->s = s;
+    }
+
+    if (hue->h < -360 || hue->h > 360)
+        av_log(ctx, AV_LOG_ERROR, "Invalid value for h:%0.1f\n", h);
+    else if (hue->s < 0 || hue->s > 2)
+        av_log(ctx, AV_LOG_ERROR, "Invalid value for s:%0.1f\n", s);
+    else {
+        /* Convert angle from degree to radian */
+        hue->h *= M_PI / 180;
+        return 0;
+    }
+
+    return AVERROR(EINVAL);
+}
+
+static int query_formats(AVFilterContext *ctx)
+{
+    static const enum PixelFormat pix_fmts[] = {
+        PIX_FMT_YUV444P,      PIX_FMT_YUV422P,
+        PIX_FMT_YUV420P,      PIX_FMT_YUV411P,
+        PIX_FMT_YUV410P,      PIX_FMT_YUV440P,
+        PIX_FMT_YUVA420P,
+        PIX_FMT_NONE
+    };
+
+    ff_set_common_formats(ctx, ff_make_format_list(pix_fmts));
+
+    return 0;
+}
+
+static int config_props(AVFilterLink *inlink)
+{
+    HueContext *hue = inlink->dst->priv;
+    const AVPixFmtDescriptor *desc = &av_pix_fmt_descriptors[inlink->format];
+
+    hue->hsub = desc->log2_chroma_w;
+    hue->vsub = desc->log2_chroma_h;
+    /*
+     * Scale the value to the norm of the resulting (U,V) vector, that is
+     * the saturation.
+     * This will be useful in the process_chrominance function.
+     */
+    hue->sin = rint(sin(hue->h) * (1 << 16) * hue->s);
+    hue->cos = rint(cos(hue->h) * (1 << 16) * hue->s);
+
+    return 0;
+}
+
+static void process_chrominance(uint8_t *udst, uint8_t *vdst, const int dst_linesize,
+                                uint8_t *usrc, uint8_t *vsrc, const int src_linesize,
+                                int w, int h,
+                                const int32_t c, const int32_t s)
+{
+    uint32_t i;
+    uint32_t u, v;
+    uint32_t new_u, new_v;
+
+    /*
+     * If we consider U and V as the components of a 2D vector then its angle
+     * is the hue and the norm is the saturation
+     */
+    while (h--) {
+        for (i = 0; i < w; i++) {
+            /* Normalize the components from range [16;140] to [-112;112] */
+            u = usrc[i] - 128;
+            v = vsrc[i] - 128;
+            /*
+             * Apply the rotation of the vector : (c * u) - (s * v)
+             *                                    (s * u) + (c * v)
+             * De-normalize the components (without forgetting to scale 128
+             * by << 16)
+             * Finally scale back the result by >> 16
+             */
+            new_u = ((c * u) - (s * v) + (1 << 15) + (128 << 16)) >> 16;
+            new_v = ((s * u) + (c * v) + (1 << 15) + (128 << 16)) >> 16;
+
+            /* Prevent a potential overflow */
+            udst[i] = av_clip_uint8_c(new_u);
+            vdst[i] = av_clip_uint8_c(new_v);
+        }
+
+        usrc += src_linesize;
+        vsrc += src_linesize;
+        udst += dst_linesize;
+        vdst += dst_linesize;
+    }
+}
+
+static int draw_slice(AVFilterLink *inlink, int y, int h, int slice_dir)
+{
+    HueContext        *hue    = inlink->dst->priv;
+    AVFilterBufferRef *inpic  = inlink->cur_buf;
+    AVFilterBufferRef *outpic = inlink->dst->outputs[0]->out_buf;
+    uint8_t *inrow[3], *outrow[3]; // 0 : Y, 1 : U, 2 : V
+    int plane;
+
+    inrow[0]  = inpic->data[0]  + y * inpic->linesize[0];
+    outrow[0] = outpic->data[0] + y * outpic->linesize[0];
+
+    for (plane = 1; plane < 3; plane++) {
+        inrow[plane]  = inpic->data[plane]  + (y >> hue->vsub) * inpic->linesize[plane];
+        outrow[plane] = outpic->data[plane] + (y >> hue->vsub) * outpic->linesize[plane];
+    }
+
+    av_image_copy_plane(outrow[0], outpic->linesize[0],
+                        inrow[0],  inpic->linesize[0],
+                        inlink->w, inlink->h);
+
+    process_chrominance(outrow[1], outrow[2], outpic->linesize[1],
+                        inrow[1], inrow[2], inpic->linesize[1],
+                        inlink->w >> hue->hsub, inlink->h >> hue->vsub,
+                        hue->cos, hue->sin);
+
+    return ff_draw_slice(inlink->dst->outputs[0], y, h, slice_dir);
+}
+
+AVFilter avfilter_vf_hue = {
+    .name        = "hue",
+    .description = NULL_IF_CONFIG_SMALL("Adjust the hue and saturation of the input video"),
+
+    .priv_size = sizeof(HueContext),
+
+    .init          = init,
+    .query_formats = query_formats,
+
+    .inputs = (const AVFilterPad[]) {{ .name             = "default",
+                                       .type             = AVMEDIA_TYPE_VIDEO,
+                                       .draw_slice       = draw_slice,
+                                       .config_props     = config_props,
+                                       .min_perms        = AV_PERM_READ },
+                                     { .name = NULL}},
+    .outputs = (const AVFilterPad[]) {{ .name             = "default",
+                                        .type             = AVMEDIA_TYPE_VIDEO },
+                                      { .name = NULL}}
+};
-- 
1.7.11.3



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