/* * Copyright (c) 2016 Clément Bœsch <u pkh me> * * 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 */ /** * @todo * - better automatic defaults? see "Parameters" @ http://www.ipol.im/pub/art/2011/bcm_nlm/ * - temporal support (probably doesn't need any displacement according to * "Denoising image sequences does not require motion estimation") * - Bayer pixel format support for at least raw photos? (DNG support would be * handy here) * - FATE test (probably needs visual threshold test mechanism due to the use * of floats) */ #include "libavutil/avassert.h" #include "libavutil/opt.h" #include "libavutil/pixdesc.h" #include "avfilter.h" #include "formats.h" #include "internal.h" #include "vf_nlmeans.h" #include "video.h" typedef struct NLMeansContext { const AVClass *class; int nb_planes; int chroma_w, chroma_h; double pdiff_scale; // invert of the filtering parameter (sigma*10) squared double sigma; // denoising strength int patch_size, patch_hsize; // patch size and half size int patch_size_uv, patch_hsize_uv; // patch size and half size for chroma planes int research_size, research_hsize; // research size and half size int research_size_uv, research_hsize_uv; // research size and half size for chroma planes uint32_t *ii_orig; // integral image uint32_t *ii; // integral image starting after the 0-line and 0-column int ii_w, ii_h; // width and height of the integral image ptrdiff_t ii_lz_32; // linesize in 32-bit units of the integral image float *total_weight; // total weight for every pixel float *sum; // weighted sum for every pixel int linesize; // sum and total_weight linesize float *weight_lut; // lookup table mapping (scaled) patch differences to their associated weights uint32_t max_meaningful_diff; // maximum difference considered (if the patch difference is too high we ignore the pixel) NLMeansDSPContext dsp; } NLMeansContext; #define OFFSET(x) offsetof(NLMeansContext, x) #define FLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM static const AVOption nlmeans_options[] = { { "s", "denoising strength", OFFSET(sigma), AV_OPT_TYPE_DOUBLE, { .dbl = 1.0 }, 1.0, 30.0, FLAGS }, { "p", "patch size", OFFSET(patch_size), AV_OPT_TYPE_INT, { .i64 = 3*2+1 }, 0, 99, FLAGS }, { "pc", "patch size for chroma planes", OFFSET(patch_size_uv), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, 99, FLAGS }, { "r", "research window", OFFSET(research_size), AV_OPT_TYPE_INT, { .i64 = 7*2+1 }, 0, 99, FLAGS }, { "rc", "research window for chroma planes", OFFSET(research_size_uv), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, 99, FLAGS }, { NULL } }; AVFILTER_DEFINE_CLASS(nlmeans); static const enum AVPixelFormat pix_fmts[] = { AV_PIX_FMT_YUV410P, AV_PIX_FMT_YUV411P, AV_PIX_FMT_YUV420P, AV_PIX_FMT_YUV422P, AV_PIX_FMT_YUV440P, AV_PIX_FMT_YUV444P, AV_PIX_FMT_YUVJ444P, AV_PIX_FMT_YUVJ440P, AV_PIX_FMT_YUVJ422P, AV_PIX_FMT_YUVJ420P, AV_PIX_FMT_YUVJ411P, AV_PIX_FMT_GRAY8, AV_PIX_FMT_GBRP, AV_PIX_FMT_NONE }; /** * Compute squared difference of the safe area (the zone where s1 and s2 * overlap). It is likely the largest integral zone, so it is interesting to do * as little checks as possible; contrary to the unsafe version of this * function, we do not need any clipping here. * * The line above dst and the column to its left are always readable. */ static void compute_safe_ssd_integral_image_c(uint32_t *dst, ptrdiff_t dst_linesize_32, const uint8_t *s1, ptrdiff_t linesize1, const uint8_t *s2, ptrdiff_t linesize2, int w, int h) { const uint32_t *dst_top = dst - dst_linesize_32; /* SIMD-friendly assumptions allowed here */ av_assert2(!(w & 0xf) && w >= 16 && h >= 1); for (int y = 0; y < h; y++) { for (int x = 0; x < w; x += 4) { const int d0 = s1[x ] - s2[x ]; const int d1 = s1[x + 1] - s2[x + 1]; const int d2 = s1[x + 2] - s2[x + 2]; const int d3 = s1[x + 3] - s2[x + 3]; dst[x ] = dst_top[x ] - dst_top[x - 1] + d0*d0; dst[x + 1] = dst_top[x + 1] - dst_top[x ] + d1*d1; dst[x + 2] = dst_top[x + 2] - dst_top[x + 1] + d2*d2; dst[x + 3] = dst_top[x + 3] - dst_top[x + 2] + d3*d3; dst[x ] += dst[x - 1]; dst[x + 1] += dst[x ]; dst[x + 2] += dst[x + 1]; dst[x + 3] += dst[x + 2]; } s1 += linesize1; s2 += linesize2; dst += dst_linesize_32; dst_top += dst_linesize_32; } } /** * Compute squared difference of an unsafe area (the zone nor s1 nor s2 could * be readable). * * On the other hand, the line above dst and the column to its left are always * readable. * * There is little point in having this function SIMDified as it is likely too * complex and only handle small portions of the image. * * @param dst integral image * @param dst_linesize_32 integral image linesize (in 32-bit integers unit) * @param startx integral starting x position * @param starty integral starting y position * @param src source plane buffer * @param linesize source plane linesize * @param offx source offsetting in x * @param offy source offsetting in y * @paran r absolute maximum source offsetting * @param sw source width * @param sh source height * @param w width to compute * @param h height to compute */ static inline void compute_unsafe_ssd_integral_image(uint32_t *dst, ptrdiff_t dst_linesize_32, int startx, int starty, const uint8_t *src, ptrdiff_t linesize, int offx, int offy, int r, int sw, int sh, int w, int h) { for (int y = starty; y < starty + h; y++) { uint32_t acc = dst[y*dst_linesize_32 + startx - 1] - dst[(y-1)*dst_linesize_32 + startx - 1]; const int s1y = av_clip(y - r, 0, sh - 1); const int s2y = av_clip(y - (r + offy), 0, sh - 1); for (int x = startx; x < startx + w; x++) { const int s1x = av_clip(x - r, 0, sw - 1); const int s2x = av_clip(x - (r + offx), 0, sw - 1); const uint8_t v1 = src[s1y*linesize + s1x]; const uint8_t v2 = src[s2y*linesize + s2x]; const int d = v1 - v2; acc += d * d; dst[y*dst_linesize_32 + x] = dst[(y-1)*dst_linesize_32 + x] + acc; } } } /* * Compute the sum of squared difference integral image * http://www.ipol.im/pub/art/2014/57/ * Integral Images for Block Matching - Gabriele Facciolo, Nicolas Limare, Enric Meinhardt-Llopis * * @param ii integral image of dimension (w+e*2) x (h+e*2) with * an additional zeroed top line and column already * "applied" to the pointer value * @param ii_linesize_32 integral image linesize (in 32-bit integers unit) * @param src source plane buffer * @param linesize source plane linesize * @param offx x-offsetting ranging in [-e;e] * @param offy y-offsetting ranging in [-e;e] * @param w source width * @param h source height * @param e research padding edge */ static void compute_ssd_integral_image(const NLMeansDSPContext *dsp, uint32_t *ii, ptrdiff_t ii_linesize_32, const uint8_t *src, ptrdiff_t linesize, int offx, int offy, int e, int w, int h) { // ii has a surrounding padding of thickness "e" const int ii_w = w + e*2; const int ii_h = h + e*2; // we center the first source const int s1x = e; const int s1y = e; // 2nd source is the frame with offsetting const int s2x = e + offx; const int s2y = e + offy; // get the dimension of the overlapping rectangle where it is always safe // to compare the 2 sources pixels const int startx_safe = FFMAX(s1x, s2x); const int starty_safe = FFMAX(s1y, s2y); const int u_endx_safe = FFMIN(s1x + w, s2x + w); // unaligned const int endy_safe = FFMIN(s1y + h, s2y + h); // deduce the safe area width and height const int safe_pw = (u_endx_safe - startx_safe) & ~0xf; const int safe_ph = endy_safe - starty_safe; // adjusted end x position of the safe area after width of the safe area gets aligned const int endx_safe = startx_safe + safe_pw; // top part where only one of s1 and s2 is still readable, or none at all compute_unsafe_ssd_integral_image(ii, ii_linesize_32, 0, 0, src, linesize, offx, offy, e, w, h, ii_w, starty_safe); // fill the left column integral required to compute the central // overlapping one compute_unsafe_ssd_integral_image(ii, ii_linesize_32, 0, starty_safe, src, linesize, offx, offy, e, w, h, startx_safe, safe_ph); // main and safe part of the integral av_assert1(startx_safe - s1x >= 0); av_assert1(startx_safe - s1x < w); av_assert1(starty_safe - s1y >= 0); av_assert1(starty_safe - s1y < h); av_assert1(startx_safe - s2x >= 0); av_assert1(startx_safe - s2x < w); av_assert1(starty_safe - s2y >= 0); av_assert1(starty_safe - s2y < h); if (safe_pw && safe_ph) dsp->compute_safe_ssd_integral_image(ii + starty_safe*ii_linesize_32 + startx_safe, ii_linesize_32, src + (starty_safe - s1y) * linesize + (startx_safe - s1x), linesize, src + (starty_safe - s2y) * linesize + (startx_safe - s2x), linesize, safe_pw, safe_ph); // right part of the integral compute_unsafe_ssd_integral_image(ii, ii_linesize_32, endx_safe, starty_safe, src, linesize, offx, offy, e, w, h, ii_w - endx_safe, safe_ph); // bottom part where only one of s1 and s2 is still readable, or none at all compute_unsafe_ssd_integral_image(ii, ii_linesize_32, 0, endy_safe, src, linesize, offx, offy, e, w, h, ii_w, ii_h - endy_safe); } static int config_input(AVFilterLink *inlink) { AVFilterContext *ctx = inlink->dst; NLMeansContext *s = ctx->priv; const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(inlink->format); const int e = FFMAX(s->research_hsize, s->research_hsize_uv) + FFMAX(s->patch_hsize, s->patch_hsize_uv); s->chroma_w = AV_CEIL_RSHIFT(inlink->w, desc->log2_chroma_w); s->chroma_h = AV_CEIL_RSHIFT(inlink->h, desc->log2_chroma_h); s->nb_planes = av_pix_fmt_count_planes(inlink->format); /* Allocate the integral image with extra edges of thickness "e" * * +_+-------------------------------+ * |0|0000000000000000000000000000000| * +-x-------------------------------+ * |0|\ ^ | * |0| ii | e | * |0| v | * |0| +-----------------------+ | * |0| | | | * |0|<->| | | * |0| e | | | * |0| | | | * |0| +-----------------------+ | * |0| | * |0| | * |0| | * +-+-------------------------------+ */ s->ii_w = inlink->w + e*2; s->ii_h = inlink->h + e*2; // align to 4 the linesize, "+1" is for the space of the left 0-column s->ii_lz_32 = FFALIGN(s->ii_w + 1, 4); // "+1" is for the space of the top 0-line s->ii_orig = av_calloc(s->ii_h + 1, s->ii_lz_32 * sizeof(*s->ii_orig)); if (!s->ii_orig) return AVERROR(ENOMEM); // skip top 0-line and left 0-column s->ii = s->ii_orig + s->ii_lz_32 + 1; // allocate weighted average for every pixel s->linesize = inlink->w + 100; s->total_weight = av_malloc_array(s->linesize, inlink->h * sizeof(*s->total_weight)); s->sum = av_malloc_array(s->linesize, inlink->h * sizeof(*s->sum)); if (!s->total_weight || !s->sum) return AVERROR(ENOMEM); return 0; } struct thread_data { const uint8_t *src; ptrdiff_t src_linesize; int startx, starty; int endx, endy; const uint32_t *ii_start; int p; }; static void compute_weights_line_c(const uint32_t *const iia, const uint32_t *const iib, const uint32_t *const iid, const uint32_t *const iie, const uint8_t *const src, float *total_weight, float *sum, const float *const weight_lut, int max_meaningful_diff, int startx, int endx) { for (int x = startx; x < endx; x++) { /* * M is a discrete map where every entry contains the sum of all the entries * in the rectangle from the top-left origin of M to its coordinate. In the * following schema, "i" contains the sum of the whole map: * * M = +----------+-----------------+----+ * | | | | * | | | | * | a| b| c| * +----------+-----------------+----+ * | | | | * | | | | * | | X | | * | | | | * | d| e| f| * +----------+-----------------+----+ * | | | | * | g| h| i| * +----------+-----------------+----+ * * The sum of the X box can be calculated with: * X = e-d-b+a * * See https://en.wikipedia.org/wiki/Summed_area_table * * The compute*_ssd functions compute the integral image M where every entry * contains the sum of the squared difference of every corresponding pixels of * two input planes of the same size as M. */ const uint32_t a = iia[x]; const uint32_t b = iib[x]; const uint32_t d = iid[x]; const uint32_t e = iie[x]; const uint32_t patch_diff_sq = FFMIN(e - d - b + a, max_meaningful_diff); const float weight = weight_lut[patch_diff_sq]; // exp(-patch_diff_sq * s->pdiff_scale) total_weight[x] += weight; sum[x] += weight * src[x]; } } static int nlmeans_slice(AVFilterContext *ctx, void *arg, int jobnr, int nb_jobs) { NLMeansContext *s = ctx->priv; const uint32_t max_meaningful_diff = s->max_meaningful_diff; const struct thread_data *td = arg; const ptrdiff_t src_linesize = td->src_linesize; const int process_h = td->endy - td->starty; const int slice_start = (process_h * jobnr ) / nb_jobs; const int slice_end = (process_h * (jobnr+1)) / nb_jobs; const int starty = td->starty + slice_start; const int endy = td->starty + slice_end; const int p = td->p; const uint32_t *ii = td->ii_start + (starty - p - 1) * s->ii_lz_32 - p - 1; const int dist_b = 2*p + 1; const int dist_d = dist_b * s->ii_lz_32; const int dist_e = dist_d + dist_b; const float *const weight_lut = s->weight_lut; NLMeansDSPContext *dsp = &s->dsp; for (int y = starty; y < endy; y++) { const uint8_t *const src = td->src + y*src_linesize; float *total_weight = s->total_weight + y*s->linesize; float *sum = s->sum + y*s->linesize; const uint32_t *const iia = ii; const uint32_t *const iib = ii + dist_b; const uint32_t *const iid = ii + dist_d; const uint32_t *const iie = ii + dist_e; dsp->compute_weights_line(iia, iib, iid, iie, src, total_weight, sum, weight_lut, max_meaningful_diff, td->startx, td->endx); ii += s->ii_lz_32; } return 0; } static void weight_averages(uint8_t *dst, ptrdiff_t dst_linesize, const uint8_t *src, ptrdiff_t src_linesize, float *total_weight, float *sum, ptrdiff_t linesize, int w, int h) { for (int y = 0; y < h; y++) { for (int x = 0; x < w; x++) { // Also weight the centered pixel total_weight[x] += 1.f; sum[x] += 1.f * src[x]; dst[x] = av_clip_uint8(sum[x] / total_weight[x] + 0.5f); } dst += dst_linesize; src += src_linesize; total_weight += linesize; sum += linesize; } } static int nlmeans_plane(AVFilterContext *ctx, int w, int h, int p, int r, uint8_t *dst, ptrdiff_t dst_linesize, const uint8_t *src, ptrdiff_t src_linesize) { NLMeansContext *s = ctx->priv; /* patches center points cover the whole research window so the patches * themselves overflow the research window */ const int e = r + p; /* focus an integral pointer on the centered image (s1) */ const uint32_t *centered_ii = s->ii + e*s->ii_lz_32 + e; memset(s->total_weight, 0, s->linesize * h * sizeof(*s->total_weight)); memset(s->sum, 0, s->linesize * h * sizeof(*s->sum)); for (int offy = -r; offy <= r; offy++) { for (int offx = -r; offx <= r; offx++) { if (offx || offy) { struct thread_data td = { .src = src + offy*src_linesize + offx, .src_linesize = src_linesize, .startx = FFMAX(0, -offx), .starty = FFMAX(0, -offy), .endx = FFMIN(w, w - offx), .endy = FFMIN(h, h - offy), .ii_start = centered_ii + offy*s->ii_lz_32 + offx, .p = p, }; compute_ssd_integral_image(&s->dsp, s->ii, s->ii_lz_32, src, src_linesize, offx, offy, e, w, h); ff_filter_execute(ctx, nlmeans_slice, &td, NULL, FFMIN(td.endy - td.starty, ff_filter_get_nb_threads(ctx))); } } } weight_averages(dst, dst_linesize, src, src_linesize, s->total_weight, s->sum, s->linesize, w, h); return 0; } static int filter_frame(AVFilterLink *inlink, AVFrame *in) { AVFilterContext *ctx = inlink->dst; NLMeansContext *s = ctx->priv; AVFilterLink *outlink = ctx->outputs[0]; 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); for (int i = 0; i < s->nb_planes; i++) { const int w = i ? s->chroma_w : inlink->w; const int h = i ? s->chroma_h : inlink->h; const int p = i ? s->patch_hsize_uv : s->patch_hsize; const int r = i ? s->research_hsize_uv : s->research_hsize; nlmeans_plane(ctx, w, h, p, r, out->data[i], out->linesize[i], in->data[i], in->linesize[i]); } av_frame_free(&in); return ff_filter_frame(outlink, out); } #define CHECK_ODD_FIELD(field, name) do { \ if (!(s->field & 1)) { \ s->field |= 1; \ av_log(ctx, AV_LOG_WARNING, name " size must be odd, " \ "setting it to %d\n", s->field); \ } \ } while (0) void ff_nlmeans_init(NLMeansDSPContext *dsp) { dsp->compute_safe_ssd_integral_image = compute_safe_ssd_integral_image_c; dsp->compute_weights_line = compute_weights_line_c; if (ARCH_AARCH64) ff_nlmeans_init_aarch64(dsp); if (ARCH_X86) ff_nlmeans_init_x86(dsp); } static av_cold int init(AVFilterContext *ctx) { NLMeansContext *s = ctx->priv; const double h = s->sigma * 10.; s->pdiff_scale = 1. / (h * h); s->max_meaningful_diff = log(255.) / s->pdiff_scale; s->weight_lut = av_calloc(s->max_meaningful_diff + 1, sizeof(*s->weight_lut)); if (!s->weight_lut) return AVERROR(ENOMEM); for (int i = 0; i < s->max_meaningful_diff; i++) s->weight_lut[i] = exp(-i * s->pdiff_scale); CHECK_ODD_FIELD(research_size, "Luma research window"); CHECK_ODD_FIELD(patch_size, "Luma patch"); if (!s->research_size_uv) s->research_size_uv = s->research_size; if (!s->patch_size_uv) s->patch_size_uv = s->patch_size; CHECK_ODD_FIELD(research_size_uv, "Chroma research window"); CHECK_ODD_FIELD(patch_size_uv, "Chroma patch"); s->research_hsize = s->research_size / 2; s->research_hsize_uv = s->research_size_uv / 2; s->patch_hsize = s->patch_size / 2; s->patch_hsize_uv = s->patch_size_uv / 2; av_log(ctx, AV_LOG_DEBUG, "Research window: %dx%d / %dx%d, patch size: %dx%d / %dx%d\n", s->research_size, s->research_size, s->research_size_uv, s->research_size_uv, s->patch_size, s->patch_size, s->patch_size_uv, s->patch_size_uv); ff_nlmeans_init(&s->dsp); return 0; } static av_cold void uninit(AVFilterContext *ctx) { NLMeansContext *s = ctx->priv; av_freep(&s->weight_lut); av_freep(&s->ii_orig); av_freep(&s->total_weight); av_freep(&s->sum); } static const AVFilterPad nlmeans_inputs[] = { { .name = "default", .type = AVMEDIA_TYPE_VIDEO, .config_props = config_input, .filter_frame = filter_frame, }, }; static const AVFilterPad nlmeans_outputs[] = { { .name = "default", .type = AVMEDIA_TYPE_VIDEO, }, }; const AVFilter ff_vf_nlmeans = { .name = "nlmeans", .description = NULL_IF_CONFIG_SMALL("Non-local means denoiser."), .priv_size = sizeof(NLMeansContext), .init = init, .uninit = uninit, FILTER_INPUTS(nlmeans_inputs), FILTER_OUTPUTS(nlmeans_outputs), FILTER_PIXFMTS_ARRAY(pix_fmts), .priv_class = &nlmeans_class, .flags = AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC | AVFILTER_FLAG_SLICE_THREADS, };