FFmpeg coverage

Directory: ../../../ffmpeg/
File: src/libavfilter/vf_gradfun.c
Date: 2025-11-02 12:19:36
Exec Total Coverage
Lines: 91 101 90.1%
Functions: 7 7 100.0%
Branches: 35 46 76.1%
Line Branch Exec Source
1 /*
2 * Copyright (c) 2010 Nolan Lum <nol888@gmail.com>
3 * Copyright (c) 2009 Loren Merritt <lorenm@u.washington.edu>
4 *
5 * This file is part of FFmpeg.
6 *
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.
11 *
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.
16 *
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
20 */
21
22 /**
23 * @file
24 * gradfun debanding filter, ported from MPlayer
25 * libmpcodecs/vf_gradfun.c
26 *
27 * Apply a boxblur debanding algorithm (based on the gradfun2db
28 * AviSynth filter by prunedtree).
29 * For each pixel, if it is within the threshold of the blurred value, make it
30 * closer. So now we have a smoothed and higher bitdepth version of all the
31 * shallow gradients, while leaving detailed areas untouched.
32 * Dither it back to 8bit.
33 */
34
35 #include "libavutil/imgutils.h"
36 #include "libavutil/common.h"
37 #include "libavutil/mem.h"
38 #include "libavutil/mem_internal.h"
39 #include "libavutil/opt.h"
40 #include "libavutil/pixdesc.h"
41 #include "avfilter.h"
42 #include "filters.h"
43 #include "gradfun.h"
44 #include "video.h"
45
46 DECLARE_ALIGNED(16, static const uint16_t, dither)[8][8] = {
47 {0x00,0x60,0x18,0x78,0x06,0x66,0x1E,0x7E},
48 {0x40,0x20,0x58,0x38,0x46,0x26,0x5E,0x3E},
49 {0x10,0x70,0x08,0x68,0x16,0x76,0x0E,0x6E},
50 {0x50,0x30,0x48,0x28,0x56,0x36,0x4E,0x2E},
51 {0x04,0x64,0x1C,0x7C,0x02,0x62,0x1A,0x7A},
52 {0x44,0x24,0x5C,0x3C,0x42,0x22,0x5A,0x3A},
53 {0x14,0x74,0x0C,0x6C,0x12,0x72,0x0A,0x6A},
54 {0x54,0x34,0x4C,0x2C,0x52,0x32,0x4A,0x2A},
55 };
56
57 32400 void ff_gradfun_filter_line_c(uint8_t *dst, const uint8_t *src, const uint16_t *dc, int width, int thresh, const uint16_t *dithers)
58 {
59 int x;
60
2/2
✓ Branch 0 taken 8755200 times.
✓ Branch 1 taken 32400 times.
 8787600 for (x = 0; x < width; dc += x & 1, x++) {
61 8755200 int pix = src[x] << 7;
62 8755200 int delta = dc[0] - pix;
63 8755200 int m = abs(delta) * thresh >> 16;
64 8755200 m = FFMAX(0, 127 - m);
65 8755200 m = m * m * delta >> 14;
66 8755200 pix += m + dithers[x & 7];
67 8755200 dst[x] = av_clip_uint8(pix >> 7);
68 }
69 32400 }
70
71 16200 void ff_gradfun_blur_line_c(uint16_t *dc, uint16_t *buf, const uint16_t *buf1, const uint8_t *src, int src_linesize, int width)
72 {
73 int x, v, old;
74
2/2
✓ Branch 0 taken 2188800 times.
✓ Branch 1 taken 16200 times.
 2205000 for (x = 0; x < width; x++) {
75 2188800 v = buf1[x] + src[2 * x] + src[2 * x + 1] + src[2 * x + src_linesize] + src[2 * x + 1 + src_linesize];
76 2188800 old = buf[x];
77 2188800 buf[x] = v;
78 2188800 dc[x] = v - old;
79 }
80 16200 }
81
82 165 static void filter(GradFunContext *ctx, uint8_t *dst, const uint8_t *src, int width, int height, int dst_linesize, int src_linesize, int r)
83 {
84 165 int bstride = FFALIGN(width, 16) / 2;
85 int y;
86 165 uint32_t dc_factor = (1 << 21) / (r * r);
87 165 uint16_t *dc = ctx->buf + 16;
88 165 uint16_t *buf = ctx->buf + bstride + 32;
89 165 int thresh = ctx->thresh;
90
91 165 memset(dc, 0, (bstride + 16) * sizeof(*buf));
92
2/2
✓ Branch 0 taken 1720 times.
✓ Branch 1 taken 165 times.
 1885 for (y = 0; y < r; y++)
93 1720 ctx->blur_line(dc, buf + y * bstride, buf + (y - 1) * bstride, src + 2 * y * src_linesize, src_linesize, width / 2);
94 for (;;) {
95
2/2
✓ Branch 0 taken 14480 times.
✓ Branch 1 taken 860 times.
 15340 if (y + 1 < height - r) {
96 14480 int mod = ((y + r) / 2) % r;
97 14480 uint16_t *buf0 = buf + mod * bstride;
98
2/2
✓ Branch 0 taken 13070 times.
✓ Branch 1 taken 1410 times.
 14480 uint16_t *buf1 = buf + (mod ? mod - 1 : r - 1) * bstride;
99 int x, v;
100 14480 ctx->blur_line(dc, buf0, buf1, src + (y + r) * src_linesize, src_linesize, width / 2);
101
2/2
✓ Branch 0 taken 167040 times.
✓ Branch 1 taken 14480 times.
 181520 for (x = v = 0; x < r; x++)
102 167040 v += dc[x];
103
2/2
✓ Branch 0 taken 1791360 times.
✓ Branch 1 taken 14480 times.
 1805840 for (; x < width / 2; x++) {
104 1791360 v += dc[x] - dc[x-r];
105 1791360 dc[x-r] = v * dc_factor >> 16;
106 }
107
2/2
✓ Branch 0 taken 83520 times.
✓ Branch 1 taken 14480 times.
 98000 for (; x < (width + r + 1) / 2; x++)
108 83520 dc[x-r] = v * dc_factor >> 16;
109
2/2
✓ Branch 0 taken 83520 times.
✓ Branch 1 taken 14480 times.
 98000 for (x = -r / 2; x < 0; x++)
110 83520 dc[x] = dc[0];
111 }
112
2/2
✓ Branch 0 taken 165 times.
✓ Branch 1 taken 15175 times.
 15340 if (y == r) {
113
2/2
✓ Branch 0 taken 1720 times.
✓ Branch 1 taken 165 times.
 1885 for (y = 0; y < r; y++)
114 1720 ctx->filter_line(dst + y * dst_linesize, src + y * src_linesize, dc - r / 2, width, thresh, dither[y & 7]);
115 }
116 15340 ctx->filter_line(dst + y * dst_linesize, src + y * src_linesize, dc - r / 2, width, thresh, dither[y & 7]);
117
1/2
✗ Branch 0 not taken.
✓ Branch 1 taken 15340 times.
 15340 if (++y >= height) break;
118 15340 ctx->filter_line(dst + y * dst_linesize, src + y * src_linesize, dc - r / 2, width, thresh, dither[y & 7]);
119
2/2
✓ Branch 0 taken 165 times.
✓ Branch 1 taken 15175 times.
 15340 if (++y >= height) break;
120 }
121 165 }
122
123 4 static av_cold int init(AVFilterContext *ctx)
124 {
125 4 GradFunContext *s = ctx->priv;
126
127 4 s->thresh = (1 << 15) / s->strength;
128 4 s->radius = av_clip((s->radius + 1) & ~1, 4, 32);
129
130 4 s->blur_line = ff_gradfun_blur_line_c;
131 4 s->filter_line = ff_gradfun_filter_line_c;
132
133 #if ARCH_X86
134 4 ff_gradfun_init_x86(s);
135 #endif
136
137 4 av_log(ctx, AV_LOG_VERBOSE, "threshold:%.2f radius:%d\n", s->strength, s->radius);
138
139 4 return 0;
140 }
141
142 4 static av_cold void uninit(AVFilterContext *ctx)
143 {
144 4 GradFunContext *s = ctx->priv;
145 4 av_freep(&s->buf);
146 4 }
147
148 static const enum AVPixelFormat pix_fmts[] = {
149 AV_PIX_FMT_YUV410P, AV_PIX_FMT_YUV420P,
150 AV_PIX_FMT_GRAY8, AV_PIX_FMT_YUV444P,
151 AV_PIX_FMT_YUV422P, AV_PIX_FMT_YUV411P,
152 AV_PIX_FMT_YUV440P,
153 AV_PIX_FMT_GBRP,
154 AV_PIX_FMT_NONE
155 };
156
157 2 static int config_input(AVFilterLink *inlink)
158 {
159 2 GradFunContext *s = inlink->dst->priv;
160 2 const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(inlink->format);
161 2 int hsub = desc->log2_chroma_w;
162 2 int vsub = desc->log2_chroma_h;
163
164 2 av_freep(&s->buf);
165 2 s->buf = av_calloc((FFALIGN(inlink->w, 16) * (s->radius + 1) / 2 + 32), sizeof(*s->buf));
166
1/2
✗ Branch 0 not taken.
✓ Branch 1 taken 2 times.
 2 if (!s->buf)
167 ✗ return AVERROR(ENOMEM);
168
169 2 s->chroma_w = AV_CEIL_RSHIFT(inlink->w, hsub);
170 2 s->chroma_h = AV_CEIL_RSHIFT(inlink->h, vsub);
171 2 s->chroma_r = av_clip(((((s->radius >> hsub) + (s->radius >> vsub)) / 2 ) + 1) & ~1, 4, 32);
172
173 2 return 0;
174 }
175
176 65 static int filter_frame(AVFilterLink *inlink, AVFrame *in)
177 {
178 65 GradFunContext *s = inlink->dst->priv;
179 65 AVFilterLink *outlink = inlink->dst->outputs[0];
180 AVFrame *out;
181 int p, direct;
182
183
1/2
✓ Branch 1 taken 65 times.
✗ Branch 2 not taken.
 65 if (av_frame_is_writable(in)) {
184 65 direct = 1;
185 65 out = in;
186 } else {
187 ✗ direct = 0;
188 ✗ out = ff_get_video_buffer(outlink, outlink->w, outlink->h);
189 ✗ if (!out) {
190 ✗ av_frame_free(&in);
191 ✗ return AVERROR(ENOMEM);
192 }
193 ✗ av_frame_copy_props(out, in);
194 }
195
196
4/6
✓ Branch 0 taken 230 times.
✗ Branch 1 not taken.
✓ Branch 2 taken 165 times.
✓ Branch 3 taken 65 times.
✓ Branch 4 taken 165 times.
✗ Branch 5 not taken.
 230 for (p = 0; p < 4 && in->data[p] && in->linesize[p]; p++) {
197 165 int w = inlink->w;
198 165 int h = inlink->h;
199 165 int r = s->radius;
200
2/2
✓ Branch 0 taken 100 times.
✓ Branch 1 taken 65 times.
 165 if (p) {
201 100 w = s->chroma_w;
202 100 h = s->chroma_h;
203 100 r = s->chroma_r;
204 }
205
206
1/2
✓ Branch 0 taken 165 times.
✗ Branch 1 not taken.
 165 if (FFMIN(w, h) > 2 * r)
207 165 filter(s, out->data[p], in->data[p], w, h, out->linesize[p], in->linesize[p], r);
208 ✗ else if (out->data[p] != in->data[p])
209 ✗ av_image_copy_plane(out->data[p], out->linesize[p], in->data[p], in->linesize[p], w, h);
210 }
211
212
1/2
✗ Branch 0 not taken.
✓ Branch 1 taken 65 times.
 65 if (!direct)
213 ✗ av_frame_free(&in);
214
215 65 return ff_filter_frame(outlink, out);
216 }
217
218 #define OFFSET(x) offsetof(GradFunContext, x)
219 #define FLAGS AV_OPT_FLAG_VIDEO_PARAM|AV_OPT_FLAG_FILTERING_PARAM
220
221 static const AVOption gradfun_options[] = {
222 { "strength", "The maximum amount by which the filter will change any one pixel.", OFFSET(strength), AV_OPT_TYPE_FLOAT, { .dbl = 1.2 }, 0.51, 64, FLAGS },
223 { "radius", "The neighborhood to fit the gradient to.", OFFSET(radius), AV_OPT_TYPE_INT, { .i64 = 16 }, 4, 32, FLAGS },
224 { NULL }
225 };
226
227 AVFILTER_DEFINE_CLASS(gradfun);
228
229 static const AVFilterPad avfilter_vf_gradfun_inputs[] = {
230 {
231 .name = "default",
232 .type = AVMEDIA_TYPE_VIDEO,
233 .config_props = config_input,
234 .filter_frame = filter_frame,
235 },
236 };
237
238 const FFFilter ff_vf_gradfun = {
239 .p.name = "gradfun",
240 .p.description = NULL_IF_CONFIG_SMALL("Debands video quickly using gradients."),
241 .p.priv_class = &gradfun_class,
242 .p.flags = AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC,
243 .priv_size = sizeof(GradFunContext),
244 .init = init,
245 .uninit = uninit,
246 FILTER_INPUTS(avfilter_vf_gradfun_inputs),
247 FILTER_OUTPUTS(ff_video_default_filterpad),
248 FILTER_PIXFMTS_ARRAY(pix_fmts),
249 };
250