[FFmpeg-devel] rectification filter
Clément Bœsch
u at pkh.me
Tue Jul 29 09:43:34 CEST 2014
On Tue, Jul 29, 2014 at 08:04:50AM +0200, Daniel Oberhoff wrote:
> Updated patch:
>
> From 204a8da14f92fcdefe63dda341261bdd25d6ce87 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] added rectification filter
>
> ---
> libavfilter/Makefile | 1 +
> libavfilter/allfilters.c | 1 +
> libavfilter/vf_rectification.c | 205 +++++++++++++++++++++++++++++++++++++++++
We have no idea what the filter does, can you add a documentation in
doc/filters.texi.
Please refer to doc/writing_filters.txt at least for the little check list
at the end.
> 3 files changed, 207 insertions(+)
> create mode 100644 libavfilter/vf_rectification.c
>
> diff --git a/libavfilter/Makefile b/libavfilter/Makefile
> index 0f54381..1488eae 100644
> --- a/libavfilter/Makefile
> +++ b/libavfilter/Makefile
> @@ -199,6 +199,7 @@ OBJS-$(CONFIG_W3FDIF_FILTER) += vf_w3fdif.o
> OBJS-$(CONFIG_YADIF_FILTER) += vf_yadif.o
> OBJS-$(CONFIG_ZMQ_FILTER) += f_zmq.o
> OBJS-$(CONFIG_ZOOMPAN_FILTER) += vf_zoompan.o
> +OBJS-$(CONFIG_RECTIFICATION_FILTER) += vf_rectification.o
>
> OBJS-$(CONFIG_CELLAUTO_FILTER) += vsrc_cellauto.o
> OBJS-$(CONFIG_COLOR_FILTER) += vsrc_testsrc.o
> diff --git a/libavfilter/allfilters.c b/libavfilter/allfilters.c
> index 1877557..f6e7bc2 100644
> --- a/libavfilter/allfilters.c
> +++ b/libavfilter/allfilters.c
> @@ -216,6 +216,7 @@ void avfilter_register_all(void)
> REGISTER_FILTER(YADIF, yadif, vf);
> REGISTER_FILTER(ZMQ, zmq, vf);
> REGISTER_FILTER(ZOOMPAN, zoompan, vf);
> + REGISTER_FILTER(RECTIFICATION, rectification, vf);
>
> REGISTER_FILTER(CELLAUTO, cellauto, vsrc);
> REGISTER_FILTER(COLOR, color, vsrc);
> diff --git a/libavfilter/vf_rectification.c b/libavfilter/vf_rectification.c
> new file mode 100644
> index 0000000..ba3a1e8
> --- /dev/null
> +++ b/libavfilter/vf_rectification.c
> @@ -0,0 +1,205 @@
> +/*
> + * Copyright (c) 2014 Daniel Oberhoff
> + *
> + * 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
> + * rectification 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"
> +
> +#include <float.h>
Is this necessary? If so, it's a system header so move it at the top with
the others.
> +
> +typedef struct RectificationCtx
> +{
> + AVClass* av_class;
Wrong style & indent. Also, the class should be const.
typedef struct RectificationCtx {
const AVClass *av_class;
> + unsigned int width;
> + unsigned int height;
> + int hsub, vsub;
> + int nb_planes;
> + double cx, cy, k1, k2;
> +} RectificationCtx;
> +
> +#define FLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM
> +static const AVOption rectification_options[] = {
> + { "cx", "set relative center x", offsetof(RectificationCtx, cx), AV_OPT_TYPE_DOUBLE, {.dbl=0.5}, 0, 1, .flags=FLAGS },
> + { "cy", "set relative center y", offsetof(RectificationCtx, cy), AV_OPT_TYPE_DOUBLE, {.dbl=0.5}, 0, 1, .flags=FLAGS },
> + { "k1", "set quadratic distortion factor", offsetof(RectificationCtx, k1), AV_OPT_TYPE_DOUBLE, {.dbl=0.5}, 0, 1, .flags=FLAGS },
> + { "k2", "set double quadratic distortion factor", offsetof(RectificationCtx, k2), AV_OPT_TYPE_DOUBLE, {.dbl=0.5}, 0, 1, .flags=FLAGS },
> + { NULL }
> +};
> +
> +AVFILTER_DEFINE_CLASS(rectification);
> +
> +static av_cold int init(AVFilterContext *ctx)
> +{
> + return 0;
> +}
> +
> +static av_cold void uninit(AVFilterContext *ctx)
> +{
> +}
> +
It doesn't work with NULL I suppose?
> +typedef struct ThreadData
> +{
> + AVFrame *in, *out;
> + int w, h;
> + int plane;
> + float xcenter, ycenter;
> + float k1, k2;
> +}ThreadData;
> +
ditto style
> +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 int 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) {
nit: i++, this is not C++
please move outrow increment out of the for for clarity
> + 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, ++out) {
ditto pre-increment
Also do the out++ when assigning the value a bit below
> + 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);
Uneeded parenthesis
> + *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_NONE
> + };
> +
> + ff_set_common_formats(ctx, ff_make_format_list(pix_fmts));
> + return 0;
> +}
> +
> +static int config_props(AVFilterLink *outlink)
> +{
> + AVFilterContext* ctx = outlink->src;
> + RectificationCtx* rect = ctx->priv;
style: * sticked to the variable, ditto in several places
> + 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];
> + RectificationCtx* rect = (RectificationCtx*)ctx->priv;
> + AVFrame* 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);
> + int plane;
Move it to the top, this is not allowed
> + 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;
> + const int w = rect->width >> hsub;
> + const int h = rect->height >> vsub;
use FF_CEIL_RSHIFT, otherwise it might cause issues with odd height/width
> + 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 rectification_inputs[] = {
> + {
> + .name = "default",
> + .type = AVMEDIA_TYPE_VIDEO,
> + .filter_frame = filter_frame,
> + },
> + { NULL }
> +};
> +
> +static const AVFilterPad rectification_outputs[] = {
> + {
> + .name = "default",
> + .type = AVMEDIA_TYPE_VIDEO,
> + .config_props = config_props,
> + },
> + { NULL }
> +};
> +
> +AVFilter ff_vf_rectification = {
> + .name = "rectification",
> + .description = NULL_IF_CONFIG_SMALL("rectify the image."),
"Rectify"
> + .priv_size = sizeof(RectificationCtx),
> + .init = init,
> + .uninit = uninit,
> + .query_formats = query_formats,
> + .process_command = NULL,
You can drop this
> + .inputs = rectification_inputs,
> + .outputs = rectification_outputs,
> + .priv_class = &rectification_class,
> + .flags = AVFILTER_FLAG_SLICE_THREADS,
> +};
--
Clément B.
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 473 bytes
Desc: not available
URL: <https://ffmpeg.org/pipermail/ffmpeg-devel/attachments/20140729/3e490ed2/attachment.asc>
More information about the ffmpeg-devel
mailing list