2 * Copyright (C) 2007 Richard Spindler (author of frei0r plugin from which this was derived)
3 * Copyright (C) 2014 Daniel Oberhoff
5 * This file is part of FFmpeg.
7 * FFmpeg is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public
9 * License as published by the Free Software Foundation; either
10 * version 2.1 of the License, or (at your option) any later version.
12 * FFmpeg is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * Lesser General Public License for more details.
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with FFmpeg; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
24 * Lenscorrection filter, algorithm from the frei0r plugin with the same name
29 #include "libavutil/opt.h"
30 #include "libavutil/intreadwrite.h"
31 #include "libavutil/pixdesc.h"
37 typedef struct LenscorrectionCtx {
38 const AVClass *av_class;
43 double cx, cy, k1, k2;
44 int32_t *correction[4];
47 #define FLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM
48 static const AVOption lenscorrection_options[] = {
49 { "cx", "set relative center x", offsetof(LenscorrectionCtx, cx), AV_OPT_TYPE_DOUBLE, {.dbl=0.5}, 0, 1, .flags=FLAGS },
50 { "cy", "set relative center y", offsetof(LenscorrectionCtx, cy), AV_OPT_TYPE_DOUBLE, {.dbl=0.5}, 0, 1, .flags=FLAGS },
51 { "k1", "set quadratic distortion factor", offsetof(LenscorrectionCtx, k1), AV_OPT_TYPE_DOUBLE, {.dbl=0.0}, -1, 1, .flags=FLAGS },
52 { "k2", "set double quadratic distortion factor", offsetof(LenscorrectionCtx, k2), AV_OPT_TYPE_DOUBLE, {.dbl=0.0}, -1, 1, .flags=FLAGS },
56 AVFILTER_DEFINE_CLASS(lenscorrection);
58 typedef struct ThreadData {
66 static int filter_slice(AVFilterContext *ctx, void *arg, int job, int nb_jobs)
70 AVFrame *out = td->out;
72 const int w = td->w, h = td->h;
73 const int xcenter = td->xcenter;
74 const int ycenter = td->ycenter;
75 const int start = (h * job ) / nb_jobs;
76 const int end = (h * (job+1)) / nb_jobs;
77 const int plane = td->plane;
78 const int inlinesize = in->linesize[plane];
79 const int outlinesize = out->linesize[plane];
80 const uint8_t *indata = in->data[plane];
81 uint8_t *outrow = out->data[plane] + start * outlinesize;
83 for (i = start; i < end; i++, outrow += outlinesize) {
84 const int off_y = i - ycenter;
85 uint8_t *out = outrow;
87 for (j = 0; j < w; j++) {
88 const int off_x = j - xcenter;
89 const int64_t radius_mult = td->correction[j + i*w];
90 const int x = xcenter + ((radius_mult * off_x + (1<<23))>>24);
91 const int y = ycenter + ((radius_mult * off_y + (1<<23))>>24);
92 const char isvalid = x > 0 && x < w - 1 && y > 0 && y < h - 1;
93 *out++ = isvalid ? indata[y * inlinesize + x] : 0;
99 static int query_formats(AVFilterContext *ctx)
101 static const enum AVPixelFormat pix_fmts[] = {
103 AV_PIX_FMT_YUV444P, AV_PIX_FMT_YUVJ444P,
104 AV_PIX_FMT_YUV420P, AV_PIX_FMT_YUVJ420P,
105 AV_PIX_FMT_YUVA444P, AV_PIX_FMT_YUVA420P,
107 AV_PIX_FMT_GBRP, AV_PIX_FMT_GBRAP,
110 AVFilterFormats *fmts_list = ff_make_format_list(pix_fmts);
112 return AVERROR(ENOMEM);
113 return ff_set_common_formats(ctx, fmts_list);
116 static av_cold void uninit(AVFilterContext *ctx)
118 LenscorrectionCtx *rect = ctx->priv;
121 for (i = 0; i < FF_ARRAY_ELEMS(rect->correction); i++) {
122 av_freep(&rect->correction[i]);
126 static int config_props(AVFilterLink *outlink)
128 AVFilterContext *ctx = outlink->src;
129 LenscorrectionCtx *rect = ctx->priv;
130 AVFilterLink *inlink = ctx->inputs[0];
131 const AVPixFmtDescriptor *pixdesc = av_pix_fmt_desc_get(inlink->format);
132 rect->hsub = pixdesc->log2_chroma_w;
133 rect->vsub = pixdesc->log2_chroma_h;
134 outlink->w = rect->width = inlink->w;
135 outlink->h = rect->height = inlink->h;
136 rect->nb_planes = av_pix_fmt_count_planes(inlink->format);
140 static int filter_frame(AVFilterLink *inlink, AVFrame *in)
142 AVFilterContext *ctx = inlink->dst;
143 AVFilterLink *outlink = ctx->outputs[0];
144 LenscorrectionCtx *rect = (LenscorrectionCtx*)ctx->priv;
145 AVFrame *out = ff_get_video_buffer(outlink, outlink->w, outlink->h);
150 return AVERROR(ENOMEM);
153 av_frame_copy_props(out, in);
155 for (plane = 0; plane < rect->nb_planes; ++plane) {
156 int hsub = plane == 1 || plane == 2 ? rect->hsub : 0;
157 int vsub = plane == 1 || plane == 2 ? rect->vsub : 0;
158 int w = AV_CEIL_RSHIFT(rect->width, hsub);
159 int h = AV_CEIL_RSHIFT(rect->height, vsub);
160 int xcenter = rect->cx * w;
161 int ycenter = rect->cy * h;
162 int k1 = rect->k1 * (1<<24);
163 int k2 = rect->k2 * (1<<24);
173 if (!rect->correction[plane]) {
175 const int64_t r2inv = (4LL<<60) / (w * w + h * h);
177 rect->correction[plane] = av_malloc_array(w, h * sizeof(**rect->correction));
178 if (!rect->correction[plane])
179 return AVERROR(ENOMEM);
180 for (j = 0; j < h; j++) {
181 const int off_y = j - ycenter;
182 const int off_y2 = off_y * off_y;
183 for (i = 0; i < w; i++) {
184 const int off_x = i - xcenter;
185 const int64_t r2 = ((off_x * off_x + off_y2) * r2inv + (1LL<<31)) >> 32;
186 const int64_t r4 = (r2 * r2 + (1<<27)) >> 28;
187 const int radius_mult = (r2 * k1 + r4 * k2 + (1LL<<27) + (1LL<<52))>>28;
188 rect->correction[plane][j * w + i] = radius_mult;
193 td.correction = rect->correction[plane];
194 ctx->internal->execute(ctx, filter_slice, &td, NULL, FFMIN(h, ff_filter_get_nb_threads(ctx)));
198 return ff_filter_frame(outlink, out);
201 static const AVFilterPad lenscorrection_inputs[] = {
204 .type = AVMEDIA_TYPE_VIDEO,
205 .filter_frame = filter_frame,
210 static const AVFilterPad lenscorrection_outputs[] = {
213 .type = AVMEDIA_TYPE_VIDEO,
214 .config_props = config_props,
219 AVFilter ff_vf_lenscorrection = {
220 .name = "lenscorrection",
221 .description = NULL_IF_CONFIG_SMALL("Rectify the image by correcting for lens distortion."),
222 .priv_size = sizeof(LenscorrectionCtx),
223 .query_formats = query_formats,
224 .inputs = lenscorrection_inputs,
225 .outputs = lenscorrection_outputs,
226 .priv_class = &lenscorrection_class,
228 .flags = AVFILTER_FLAG_SLICE_THREADS,