| 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 | * Foreach pixel, if it's within threshold of the blurred value, make it closer. |
| 30 | * So now we have a smoothed and higher bitdepth version of all the shallow |
| 31 | * 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/cpu.h" |
| 38 | #include "libavutil/opt.h" |
| 39 | #include "libavutil/pixdesc.h" |
| 40 | #include "avfilter.h" |
| 41 | #include "formats.h" |
| 42 | #include "gradfun.h" |
| 43 | #include "internal.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 | 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 | for (x = 0; x < width; dc += x & 1, x++) { |
| 61 | int pix = src[x] << 7; |
| 62 | int delta = dc[0] - pix; |
| 63 | int m = abs(delta) * thresh >> 16; |
| 64 | m = FFMAX(0, 127 - m); |
| 65 | m = m * m * delta >> 14; |
| 66 | pix += m + dithers[x & 7]; |
| 67 | dst[x] = av_clip_uint8(pix >> 7); |
| 68 | } |
| 69 | } |
| 70 | |
| 71 | 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 | for (x = 0; x < width; x++) { |
| 75 | v = buf1[x] + src[2 * x] + src[2 * x + 1] + src[2 * x + src_linesize] + src[2 * x + 1 + src_linesize]; |
| 76 | old = buf[x]; |
| 77 | buf[x] = v; |
| 78 | dc[x] = v - old; |
| 79 | } |
| 80 | } |
| 81 | |
| 82 | 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 | int bstride = FFALIGN(width, 16) / 2; |
| 85 | int y; |
| 86 | uint32_t dc_factor = (1 << 21) / (r * r); |
| 87 | uint16_t *dc = ctx->buf + 16; |
| 88 | uint16_t *buf = ctx->buf + bstride + 32; |
| 89 | int thresh = ctx->thresh; |
| 90 | |
| 91 | memset(dc, 0, (bstride + 16) * sizeof(*buf)); |
| 92 | for (y = 0; y < r; y++) |
| 93 | ctx->blur_line(dc, buf + y * bstride, buf + (y - 1) * bstride, src + 2 * y * src_linesize, src_linesize, width / 2); |
| 94 | for (;;) { |
| 95 | if (y < height - r) { |
| 96 | int mod = ((y + r) / 2) % r; |
| 97 | uint16_t *buf0 = buf + mod * bstride; |
| 98 | uint16_t *buf1 = buf + (mod ? mod - 1 : r - 1) * bstride; |
| 99 | int x, v; |
| 100 | ctx->blur_line(dc, buf0, buf1, src + (y + r) * src_linesize, src_linesize, width / 2); |
| 101 | for (x = v = 0; x < r; x++) |
| 102 | v += dc[x]; |
| 103 | for (; x < width / 2; x++) { |
| 104 | v += dc[x] - dc[x-r]; |
| 105 | dc[x-r] = v * dc_factor >> 16; |
| 106 | } |
| 107 | for (; x < (width + r + 1) / 2; x++) |
| 108 | dc[x-r] = v * dc_factor >> 16; |
| 109 | for (x = -r / 2; x < 0; x++) |
| 110 | dc[x] = dc[0]; |
| 111 | } |
| 112 | if (y == r) { |
| 113 | for (y = 0; y < r; y++) |
| 114 | ctx->filter_line(dst + y * dst_linesize, src + y * src_linesize, dc - r / 2, width, thresh, dither[y & 7]); |
| 115 | } |
| 116 | ctx->filter_line(dst + y * dst_linesize, src + y * src_linesize, dc - r / 2, width, thresh, dither[y & 7]); |
| 117 | if (++y >= height) break; |
| 118 | ctx->filter_line(dst + y * dst_linesize, src + y * src_linesize, dc - r / 2, width, thresh, dither[y & 7]); |
| 119 | if (++y >= height) break; |
| 120 | } |
| 121 | emms_c(); |
| 122 | } |
| 123 | |
| 124 | static av_cold int init(AVFilterContext *ctx) |
| 125 | { |
| 126 | GradFunContext *s = ctx->priv; |
| 127 | |
| 128 | s->thresh = (1 << 15) / s->strength; |
| 129 | s->radius = av_clip((s->radius + 1) & ~1, 4, 32); |
| 130 | |
| 131 | s->blur_line = ff_gradfun_blur_line_c; |
| 132 | s->filter_line = ff_gradfun_filter_line_c; |
| 133 | |
| 134 | if (ARCH_X86) |
| 135 | ff_gradfun_init_x86(s); |
| 136 | |
| 137 | av_log(ctx, AV_LOG_VERBOSE, "threshold:%.2f radius:%d\n", s->strength, s->radius); |
| 138 | |
| 139 | return 0; |
| 140 | } |
| 141 | |
| 142 | static av_cold void uninit(AVFilterContext *ctx) |
| 143 | { |
| 144 | GradFunContext *s = ctx->priv; |
| 145 | av_freep(&s->buf); |
| 146 | } |
| 147 | |
| 148 | static int query_formats(AVFilterContext *ctx) |
| 149 | { |
| 150 | static const enum AVPixelFormat pix_fmts[] = { |
| 151 | AV_PIX_FMT_YUV410P, AV_PIX_FMT_YUV420P, |
| 152 | AV_PIX_FMT_GRAY8, AV_PIX_FMT_YUV444P, |
| 153 | AV_PIX_FMT_YUV422P, AV_PIX_FMT_YUV411P, |
| 154 | AV_PIX_FMT_YUV440P, |
| 155 | AV_PIX_FMT_GBRP, |
| 156 | AV_PIX_FMT_NONE |
| 157 | }; |
| 158 | |
| 159 | ff_set_common_formats(ctx, ff_make_format_list(pix_fmts)); |
| 160 | |
| 161 | return 0; |
| 162 | } |
| 163 | |
| 164 | static int config_input(AVFilterLink *inlink) |
| 165 | { |
| 166 | GradFunContext *s = inlink->dst->priv; |
| 167 | const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(inlink->format); |
| 168 | int hsub = desc->log2_chroma_w; |
| 169 | int vsub = desc->log2_chroma_h; |
| 170 | |
| 171 | av_freep(&s->buf); |
| 172 | s->buf = av_calloc((FFALIGN(inlink->w, 16) * (s->radius + 1) / 2 + 32), sizeof(*s->buf)); |
| 173 | if (!s->buf) |
| 174 | return AVERROR(ENOMEM); |
| 175 | |
| 176 | s->chroma_w = FF_CEIL_RSHIFT(inlink->w, hsub); |
| 177 | s->chroma_h = FF_CEIL_RSHIFT(inlink->h, vsub); |
| 178 | s->chroma_r = av_clip(((((s->radius >> hsub) + (s->radius >> vsub)) / 2 ) + 1) & ~1, 4, 32); |
| 179 | |
| 180 | return 0; |
| 181 | } |
| 182 | |
| 183 | static int filter_frame(AVFilterLink *inlink, AVFrame *in) |
| 184 | { |
| 185 | GradFunContext *s = inlink->dst->priv; |
| 186 | AVFilterLink *outlink = inlink->dst->outputs[0]; |
| 187 | AVFrame *out; |
| 188 | int p, direct; |
| 189 | |
| 190 | if (av_frame_is_writable(in)) { |
| 191 | direct = 1; |
| 192 | out = in; |
| 193 | } else { |
| 194 | direct = 0; |
| 195 | out = ff_get_video_buffer(outlink, outlink->w, outlink->h); |
| 196 | if (!out) { |
| 197 | av_frame_free(&in); |
| 198 | return AVERROR(ENOMEM); |
| 199 | } |
| 200 | av_frame_copy_props(out, in); |
| 201 | } |
| 202 | |
| 203 | for (p = 0; p < 4 && in->data[p] && in->linesize[p]; p++) { |
| 204 | int w = inlink->w; |
| 205 | int h = inlink->h; |
| 206 | int r = s->radius; |
| 207 | if (p) { |
| 208 | w = s->chroma_w; |
| 209 | h = s->chroma_h; |
| 210 | r = s->chroma_r; |
| 211 | } |
| 212 | |
| 213 | if (FFMIN(w, h) > 2 * r) |
| 214 | filter(s, out->data[p], in->data[p], w, h, out->linesize[p], in->linesize[p], r); |
| 215 | else if (out->data[p] != in->data[p]) |
| 216 | av_image_copy_plane(out->data[p], out->linesize[p], in->data[p], in->linesize[p], w, h); |
| 217 | } |
| 218 | |
| 219 | if (!direct) |
| 220 | av_frame_free(&in); |
| 221 | |
| 222 | return ff_filter_frame(outlink, out); |
| 223 | } |
| 224 | |
| 225 | #define OFFSET(x) offsetof(GradFunContext, x) |
| 226 | #define FLAGS AV_OPT_FLAG_VIDEO_PARAM|AV_OPT_FLAG_FILTERING_PARAM |
| 227 | |
| 228 | static const AVOption gradfun_options[] = { |
| 229 | { "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 }, |
| 230 | { "radius", "The neighborhood to fit the gradient to.", OFFSET(radius), AV_OPT_TYPE_INT, { .i64 = 16 }, 4, 32, FLAGS }, |
| 231 | { NULL } |
| 232 | }; |
| 233 | |
| 234 | AVFILTER_DEFINE_CLASS(gradfun); |
| 235 | |
| 236 | static const AVFilterPad avfilter_vf_gradfun_inputs[] = { |
| 237 | { |
| 238 | .name = "default", |
| 239 | .type = AVMEDIA_TYPE_VIDEO, |
| 240 | .config_props = config_input, |
| 241 | .filter_frame = filter_frame, |
| 242 | }, |
| 243 | { NULL } |
| 244 | }; |
| 245 | |
| 246 | static const AVFilterPad avfilter_vf_gradfun_outputs[] = { |
| 247 | { |
| 248 | .name = "default", |
| 249 | .type = AVMEDIA_TYPE_VIDEO, |
| 250 | }, |
| 251 | { NULL } |
| 252 | }; |
| 253 | |
| 254 | AVFilter ff_vf_gradfun = { |
| 255 | .name = "gradfun", |
| 256 | .description = NULL_IF_CONFIG_SMALL("Debands video quickly using gradients."), |
| 257 | .priv_size = sizeof(GradFunContext), |
| 258 | .priv_class = &gradfun_class, |
| 259 | .init = init, |
| 260 | .uninit = uninit, |
| 261 | .query_formats = query_formats, |
| 262 | .inputs = avfilter_vf_gradfun_inputs, |
| 263 | .outputs = avfilter_vf_gradfun_outputs, |
| 264 | .flags = AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC, |
| 265 | }; |