[FFmpeg-devel] rectification filter
Daniel Oberhoff
danieloberhoff at gmail.com
Sun Aug 3 17:39:38 CEST 2014
Am 03.08.2014 um 03:15 schrieb Daniel Oberhoff <danieloberhoff at googlemail.com>:
> Am 03.08.2014 um 00:12 schrieb Clément Bœsch <u at pkh.me>:
>
>> On Fri, Aug 01, 2014 at 12:56:42PM +0200, Daniel Oberhoff wrote:
>>>
>>> Am 01.08.2014 um 12:22 schrieb Clément Bœsch <u at pkh.me>:
>>>
>>>> On Fri, Aug 01, 2014 at 12:13:22PM +0200, Daniel Oberhoff wrote:
>>>>>
>>>>> Am 29.07.2014 um 09:54 schrieb Carl Eugen Hoyos <cehoyos at ag.or.at>:
>>>>>
>>>>>> Daniel Oberhoff <danieloberhoff <at> gmail.com> writes:
>>>>>>
>>>>>>> OBJS-$(CONFIG_ZOOMPAN_FILTER) += vf_zoompan.o
>>>>>>> +OBJS-$(CONFIG_RECTIFICATION_FILTER) += vf_rectification.o
>>>>>>
>>>>>>> REGISTER_FILTER(ZOOMPAN, zoompan, vf);
>>>>>>> + REGISTER_FILTER(RECTIFICATION, rectification, vf);
>>>>>>
>>>>>> Keep the alphabetic ordering please.
>>>>>>
>>>>>
>>>>> Ok
>>>>>
>>>>>>> + AV_PIX_FMT_YUV410P,
>>>>>>> + AV_PIX_FMT_YUV444P, AV_PIX_FMT_YUVJ444P,
>>>>>>> + AV_PIX_FMT_YUV420P, AV_PIX_FMT_YUVJ420P,
>>>>>>> + AV_PIX_FMT_YUVA444P, AV_PIX_FMT_YUVA420P,
>>>>>>> + AV_PIX_FMT_NONE
>>>>>>
>>>>>> I have no idea what this filter does and since the
>>>>>> most important format (yuv420p) is supported, this
>>>>>> doesn't really matter but yuv410p and yuva444p are
>>>>>> quite exotic formats, I would at least have
>>>>>> expected yuv422p, yuva420p and yuv444p in the list.
>>>>>>
>>>>>> Did you test all above formats (at least the left row)?
>>>>>
>>>>> Added the one from your list that was missing. Can you suggest an easy way of testing all these formats?
>>>>>
>>>>
>>>>
>>>> add a format filter before yours in the filtergraph (-vf
>>>> format=yuv410p,rectification …)
>>>
>>> Ok, borders can be a bitt different, but otherwise all work now, except vuy444p, which ffmpeg reports as invalid. btw, how can I get the components of a given color in the colorspace?
>>>
>>>> If you want to add a FATE test (which would be really awesome), you can
>>>> grep for "video_filter" in tests/fate/filter-video.mak (to test all pixel
>>>> formats the filter supports), or just make a standard test with framecrc.
>>>>
>>>> [...]
>>>
>>> I did that by adding this:
>>>
>>> FATE_FILTER_PIXFMTS-$(CONFIG_RECTIFICATION_FILTER) += fate-filter-pixfmts-rectification
>>> fate-filter-pixfmts-rectification: CMD = pixfmts "0.6:0.4:0.65:0.4"
>>>
>>> then I ran
>>>
>>> make fate-filter-pixfmts-rectification GEN=1
>>>
>>> which made a file
>>>
>>> test/data/fate/filter-pixfmts-rectification.rep
>>>
>>
>> This is the result of a normal run to be compared by with the reference
>> which should have also been generated with the help of GEN=1 for your
>> first run. The file(s) generated by GEN=1 need to be tracked.
>>
>>> do I check this in or not?
>>>
>>
>> Of course you are supposed to check if the results make sense.
>>
>> Use make fate-filter-pixfmts-rectifications V=1 to see what's going on.
>>
>>> running
>>>
>>> make fate-filter-pixfmts-rectification GEN=1
>>>
>>> runs fine…
>>>
>>
>> Of course, it doesn't do the comparison, it generates the reference.
>>
>>> Best
>>>
>>> Daniel
>>
>> --
>> Clément B.
>> _______________________________________________
>> ffmpeg-devel mailing list
>> ffmpeg-devel at ffmpeg.org
>> http://ffmpeg.org/mailman/listinfo/ffmpeg-devel
>
> Alright, will get that cleaned up. Since I seem to have all consent I need to also change the license I will see that I get a new patch ready soon.
>
> Best and thanks for feedback!
>
> Daniel
Hello all,
I updated the patch trying to incorporate all review feedback. I also got consent from the original author to put this filter under LGPL, and thus have it compiled in by default. I also conversed with Cyrille from Krita
and he doesn’t see any more copyright issues, as at that point it boils down to the use of a well known algorithm, in a straight-forward implementation.
Compared to the previous patch I renamed the filter to lenscorrection, since that is the name in the frei0r suite, and it will make using this instead of the frei0r one as easy as stating
lenscorrection=...
instead of
frei0r=lenscorrection:...
Last but not least I adapted the format list, inspected results on all formats, and supplied a fate test. Release notes and docs where also adapted. Please check if this is ok to push now.
From dc552ae06a41725988250896327af2cceee1b812 Mon Sep 17 00:00:00 2001
From: Daniel Oberhoff <daniel at danieloberhoff.de>
Date: Mon, 28 Jul 2014 23:58:12 +0200
Subject: [PATCH] ported lenscorrection filter from frei0r
---
Changelog | 2 +-
doc/filters.texi | 36 +++++
libavfilter/Makefile | 1 +
libavfilter/allfilters.c | 1 +
libavfilter/version.h | 4 +-
libavfilter/vf_lenscorrection.c | 208 +++++++++++++++++++++++++++
tests/fate/filter-video.mak | 3 +
tests/ref/fate/filter-pixfmts-lenscorrection | 8 ++
8 files changed, 260 insertions(+), 3 deletions(-)
create mode 100644 libavfilter/vf_lenscorrection.c
create mode 100644 tests/ref/fate/filter-pixfmts-lenscorrection
diff --git a/Changelog b/Changelog
index 067f72a..3c1ee51 100644
--- a/Changelog
+++ b/Changelog
@@ -2,7 +2,7 @@ Entries are sorted chronologically from oldest to youngest within each release,
releases are sorted from youngest to oldest.
version <next>:
-
+- ported lenscorrection filter from frei0r filter
version 2.3:
- AC3 fixed-point decoding
diff --git a/doc/filters.texi b/doc/filters.texi
index c5caa77..2af311a 100644
--- a/doc/filters.texi
+++ b/doc/filters.texi
@@ -5532,6 +5532,42 @@ kerndeint=map=1
@end example
@end itemize
+ at section lenscorrection
+
+This filter can be used to correct for radial distortion as can result from the use
+of wide angle lenses, and thereby re-rectify the image. To find the right parameters
+one can use tools available for example as part of opencv or simply trial-and-error.
+Note that effectively the same filter is available in the open-source tools Krita and
+Digikam from the KDE project.
+In contrast to the vignette filter, which can also be used to compensate lens errors,
+this filter corrects the distortion of the image, whereas vignette corrects the
+brightness distribution, so you may want to use both filters together in certain
+cases, though you will have to take care of ordering, i.e. wether vignette should
+be applied before or after lenscorrection.
+
+The filter accepts the following options:
+
+ at table @option
+ at item cx
+Relative x-coordinate of the focal point of the image, and thereby the center of the
+distrortion. This value has a range [0,1] and is expressed as fractions of the image
+width.
+ at item cy
+Relative y-coordinate of the focal point of the image, and thereby the center of the
+distrortion. This value has a range [0,1] and is expressed as fractions of the image
+height.
+ at item k1
+Coefficient of the quadratic correction term. 0.5 means no correction.
+ at item k2
+Coefficient of the double quadratic correction term. 0.5 means no correction.
+ at end table
+
+The formula that generates the correction is:
+
+r_src = r_tgt * (1 + (k1 - 0.5) * (r_tgt/r_0)^2 + (k2 - 0.5) * (r_tgt/r_0)^4)
+
+where r_0 is halve of the image diagonal.
+
@anchor{lut3d}
@section lut3d
diff --git a/libavfilter/Makefile b/libavfilter/Makefile
index 0f54381..f74defa 100644
--- a/libavfilter/Makefile
+++ b/libavfilter/Makefile
@@ -162,6 +162,7 @@ OBJS-$(CONFIG_PIXDESCTEST_FILTER) += vf_pixdesctest.o
OBJS-$(CONFIG_PP_FILTER) += vf_pp.o
OBJS-$(CONFIG_PSNR_FILTER) += vf_psnr.o dualinput.o framesync.o
OBJS-$(CONFIG_PULLUP_FILTER) += vf_pullup.o
+OBJS-$(CONFIG_LENSCORRECTION_FILTER) += vf_lenscorrection.o
OBJS-$(CONFIG_REMOVELOGO_FILTER) += bbox.o lswsutils.o lavfutils.o vf_removelogo.o
OBJS-$(CONFIG_ROTATE_FILTER) += vf_rotate.o
OBJS-$(CONFIG_SEPARATEFIELDS_FILTER) += vf_separatefields.o
diff --git a/libavfilter/allfilters.c b/libavfilter/allfilters.c
index 1877557..b1d6ff5 100644
--- a/libavfilter/allfilters.c
+++ b/libavfilter/allfilters.c
@@ -156,6 +156,7 @@ void avfilter_register_all(void)
REGISTER_FILTER(INTERLACE, interlace, vf);
REGISTER_FILTER(INTERLEAVE, interleave, vf);
REGISTER_FILTER(KERNDEINT, kerndeint, vf);
+ REGISTER_FILTER(LENSCORRECTION, lenscorrection, vf);
REGISTER_FILTER(LUT3D, lut3d, vf);
REGISTER_FILTER(LUT, lut, vf);
REGISTER_FILTER(LUTRGB, lutrgb, vf);
diff --git a/libavfilter/version.h b/libavfilter/version.h
index 1a43dc5..47bac78 100644
--- a/libavfilter/version.h
+++ b/libavfilter/version.h
@@ -30,8 +30,8 @@
#include "libavutil/version.h"
#define LIBAVFILTER_VERSION_MAJOR 4
-#define LIBAVFILTER_VERSION_MINOR 11
-#define LIBAVFILTER_VERSION_MICRO 102
+#define LIBAVFILTER_VERSION_MINOR 12
+#define LIBAVFILTER_VERSION_MICRO 100
#define LIBAVFILTER_VERSION_INT AV_VERSION_INT(LIBAVFILTER_VERSION_MAJOR, \
LIBAVFILTER_VERSION_MINOR, \
diff --git a/libavfilter/vf_lenscorrection.c b/libavfilter/vf_lenscorrection.c
new file mode 100644
index 0000000..1aad94c
--- /dev/null
+++ b/libavfilter/vf_lenscorrection.c
@@ -0,0 +1,208 @@
+/*
+ * Copyright (c) 2014 Daniel Oberhoff
+ * Copyright (C) 2007 Richard Spindler (author of frei0r plugin from which this was derived)
+ *
+ * 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
+ */
+
+/**
+ * @file
+ * Lenscorrection filter, algorithm from the frei0r plugin with the same name
+*/
+#include <stdlib.h>
+#include <math.h>
+
+#include "libavutil/opt.h"
+#include "libavutil/intreadwrite.h"
+#include "libavutil/pixdesc.h"
+
+#include "avfilter.h"
+#include "internal.h"
+#include "video.h"
+
+typedef struct LenscorrectionCtx {
+ const AVClass* av_class;
+ unsigned int width;
+ unsigned int height;
+ int hsub, vsub;
+ int nb_planes;
+ double cx, cy, k1, k2;
+} LenscorrectionCtx;
+
+#define FLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM
+static const AVOption Lenscorrection_options[] = {
+ { "cx", "set relative center x", offsetof(LenscorrectionCtx, cx), AV_OPT_TYPE_DOUBLE, {.dbl=0.5}, 0, 1, .flags=FLAGS },
+ { "cy", "set relative center y", offsetof(LenscorrectionCtx, cy), AV_OPT_TYPE_DOUBLE, {.dbl=0.5}, 0, 1, .flags=FLAGS },
+ { "k1", "set quadratic distortion factor", offsetof(LenscorrectionCtx, k1), AV_OPT_TYPE_DOUBLE, {.dbl=0.5}, 0, 1, .flags=FLAGS },
+ { "k2", "set double quadratic distortion factor", offsetof(LenscorrectionCtx, k2), AV_OPT_TYPE_DOUBLE, {.dbl=0.5}, 0, 1, .flags=FLAGS },
+ { NULL }
+};
+
+AVFILTER_DEFINE_CLASS(Lenscorrection);
+
+static av_cold int init(AVFilterContext *ctx)
+{
+ return 0;
+}
+
+static av_cold void uninit(AVFilterContext *ctx)
+{
+}
+
+typedef struct ThreadData {
+ AVFrame *in, *out;
+ float w, h;
+ int plane;
+ float xcenter, ycenter;
+ float k1, k2;
+} ThreadData;
+
+static int filter_slice(AVFilterContext *ctx, void *arg, int job, int nb_jobs)
+{
+ ThreadData *td = (ThreadData*)arg;
+ AVFrame *in = td->in;
+ AVFrame *out = td->out;
+
+ const float w = td->w, h = td->h;
+ const float xcenter = td->xcenter;
+ const float ycenter = td->ycenter;
+ const float r2inv = 4.0 / (w * w + h * h);
+ const float k1 = td->k1 - 0.5;
+ const float k2 = td->k2 - 0.5;
+ const int start = (h * job ) / nb_jobs;
+ const int end = (h * (job+1)) / nb_jobs;
+ const int plane = td->plane;
+ const int inlinesize = in->linesize[plane];
+ const int outlinesize = out->linesize[plane];
+ const uint8_t *indata = in->data[plane];
+ uint8_t *outrow = out->data[plane] + start * outlinesize;
+ int i;
+ for (i = start; i < end; i++, outrow += outlinesize) {
+ const float off_y = i - ycenter;
+ const float off_y2 = off_y * off_y;
+ uint8_t *out = outrow;
+ int j;
+ for (j = 0; j < w; j++) {
+ const float off_x = j - xcenter;
+ const float r2 = (off_x * off_x + off_y2) * r2inv;
+ const float radius_mult = 1.0f + r2 * k1 + r2 * r2 * k2;
+ const int x = xcenter + radius_mult * off_x + 0.5f;
+ const int y = ycenter + radius_mult * off_y + 0.5f;
+ const char isvalid = x > 0 && x < w - 1 && y > 0 && y < h - 1;
+ *out++ = isvalid ? indata[y * inlinesize + x] : 0;
+ }
+ }
+ return 0;
+}
+
+static int query_formats(AVFilterContext *ctx)
+{
+ static enum PixelFormat pix_fmts[] = {
+ AV_PIX_FMT_YUV410P,
+ AV_PIX_FMT_YUV444P, AV_PIX_FMT_YUVJ444P,
+ AV_PIX_FMT_YUV420P, AV_PIX_FMT_YUVJ420P,
+ AV_PIX_FMT_YUVA444P, AV_PIX_FMT_YUVA420P,
+ AV_PIX_FMT_YUV422P,
+ AV_PIX_FMT_NONE
+ };
+
+ ff_set_common_formats(ctx, ff_make_format_list(pix_fmts));
+ return 0;
+}
+
+static int config_props(AVFilterLink *outlink)
+{
+ AVFilterContext* ctx = outlink->src;
+ LenscorrectionCtx* rect = ctx->priv;
+ AVFilterLink *inlink = ctx->inputs[0];
+ const AVPixFmtDescriptor *pixdesc = av_pix_fmt_desc_get(inlink->format);
+ rect->hsub = pixdesc->log2_chroma_w;
+ rect->vsub = pixdesc->log2_chroma_h;
+ outlink->w = rect->width = inlink->w;
+ outlink->h = rect->height = inlink->h;
+ rect->nb_planes = av_pix_fmt_count_planes(inlink->format);
+ return 0;
+}
+
+static int filter_frame(AVFilterLink *inlink, AVFrame *in)
+{
+ AVFilterContext *ctx = inlink->dst;
+ AVFilterLink *outlink = ctx->outputs[0];
+ LenscorrectionCtx *rect = (LenscorrectionCtx*)ctx->priv;
+ AVFrame* out = ff_get_video_buffer(outlink, outlink->w, outlink->h);
+ int plane;
+
+ if (!out) {
+ av_frame_free(&in);
+ return AVERROR(ENOMEM);
+ }
+
+ av_frame_copy_props(out, in);
+
+ for (plane = 0; plane < rect->nb_planes; ++plane) {
+ int hsub = plane == 1 || plane == 2 ? rect->hsub : 0;
+ int vsub = plane == 1 || plane == 2 ? rect->vsub : 0;
+ float hdiv = 1 << hsub;
+ float vdiv = 1 << vsub;
+ float w = rect->width / hdiv;
+ float h = rect->height / vdiv;
+ ThreadData td = { .in = in, .out = out,
+ .w = w,
+ .h = h,
+ .xcenter = rect->cx * w,
+ .ycenter = rect->cy * h,
+ .k1 = rect->k1,
+ .k2 = rect->k2,
+ .plane = plane};
+ ctx->internal->execute(ctx, filter_slice, &td, NULL, FFMIN(h, ctx->graph->nb_threads));
+ }
+
+ av_frame_free(&in);
+ return ff_filter_frame(outlink, out);
+}
+
+static const AVFilterPad Lenscorrection_inputs[] = {
+ {
+ .name = "default",
+ .type = AVMEDIA_TYPE_VIDEO,
+ .filter_frame = filter_frame,
+ },
+ { NULL }
+};
+
+static const AVFilterPad Lenscorrection_outputs[] = {
+ {
+ .name = "default",
+ .type = AVMEDIA_TYPE_VIDEO,
+ .config_props = config_props,
+ },
+ { NULL }
+};
+
+AVFilter ff_vf_lenscorrection = {
+ .name = "lenscorrection",
+ .description = NULL_IF_CONFIG_SMALL("Rectify the image by correcting for lens distortion."),
+ .priv_size = sizeof(LenscorrectionCtx),
+ .init = init,
+ .uninit = uninit,
+ .query_formats = query_formats,
+ .inputs = Lenscorrection_inputs,
+ .outputs = Lenscorrection_outputs,
+ .priv_class = &Lenscorrection_class,
+ .flags = AVFILTER_FLAG_SLICE_THREADS,
+};
+
\ No newline at end of file
diff --git a/tests/fate/filter-video.mak b/tests/fate/filter-video.mak
index d87129b..cc5a71b 100644
--- a/tests/fate/filter-video.mak
+++ b/tests/fate/filter-video.mak
@@ -331,6 +331,9 @@ fate-filter-pixfmts-il: CMD = pixfmts "luma_mode=d:chroma_mode=d:alpha_mode=d
FATE_FILTER_PIXFMTS-$(CONFIG_KERNDEINT_FILTER) += fate-filter-pixfmts-kerndeint
fate-filter-pixfmts-kerndeint: CMD = pixfmts "" "tinterlace=interleave_top,"
+FATE_FILTER_PIXFMTS-$(CONFIG_LENSCORRECTION_FILTER) += fate-filter-pixfmts-lenscorrection
+fate-filter-pixfmts-lenscorrection: CMD = pixfmts "0.6:0.4:0.65:0.4"
+
FATE_FILTER_PIXFMTS-$(CONFIG_LUT_FILTER) += fate-filter-pixfmts-lut
fate-filter-pixfmts-lut: CMD = pixfmts "c0=2*val:c1=2*val:c2=val/2:c3=negval+40"
diff --git a/tests/ref/fate/filter-pixfmts-lenscorrection b/tests/ref/fate/filter-pixfmts-lenscorrection
new file mode 100644
index 0000000..18af6fb
--- /dev/null
+++ b/tests/ref/fate/filter-pixfmts-lenscorrection
@@ -0,0 +1,8 @@
+yuv410p e7d59dbdb1afab7e2a8f770d563e28c4
+yuv420p bc45b4762d5271410ff825317c85af64
+yuv422p 5cce0c299322634d65e6b32c976e2c12
+yuv444p 03de9a93ab3045a523b234ea93f21c91
+yuva420p d1fa6735c4e7fbbf3a501cec1f0b4ac1
+yuva444p 713ddf5861d3df11c70a242a13c5e92e
+yuvj420p 1d5cccaf4ef568ae9fa36f9a28e71c34
+yuvj444p aef1db29848e3b1dcaf4309255c38cbd
--
1.8.2
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