/**
* @todo
- * - SIMD for compute_safe_ssd_integral_image
- * - SIMD for final weighted averaging
* - 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")
#include "avfilter.h"
#include "formats.h"
#include "internal.h"
+#include "vf_nlmeans.h"
#include "video.h"
struct weighted_avg {
- double total_weight;
- double sum;
+ float total_weight;
+ float sum;
};
-#define WEIGHT_LUT_NBITS 9
-#define WEIGHT_LUT_SIZE (1<<WEIGHT_LUT_NBITS)
-
typedef struct NLMeansContext {
const AVClass *class;
int nb_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
- int ii_lz_32; // linesize in 32-bit units of the integral image
+ ptrdiff_t ii_lz_32; // linesize in 32-bit units of the integral image
struct weighted_avg *wa; // weighted average of every pixel
- int wa_linesize; // linesize for wa in struct size unit
- double weight_lut[WEIGHT_LUT_SIZE]; // lookup table mapping (scaled) patch differences to their associated weights
- double pdiff_lut_scale; // scale factor for patch differences before looking into the LUT
- int max_meaningful_diff; // maximum difference considered (if the patch difference is too high we ignore the pixel)
+ ptrdiff_t wa_linesize; // linesize for wa in struct size unit
+ 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)
return ff_set_common_formats(ctx, fmts_list);
}
-/*
- * 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.
- */
-static inline int get_integral_patch_value(const uint32_t *ii, int ii_lz_32, int x, int y, int p)
-{
- const int e = ii[(y + p ) * ii_lz_32 + (x + p )];
- const int d = ii[(y + p ) * ii_lz_32 + (x - p - 1)];
- const int b = ii[(y - p - 1) * ii_lz_32 + (x + p )];
- const int a = ii[(y - p - 1) * ii_lz_32 + (x - p - 1)];
- return e - d - b + a;
-}
-
/**
* 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
* function, we do not need any clipping here.
*
* The line above dst and the column to its left are always readable.
- *
- * This C version computes the SSD integral image using a scalar accumulator,
- * while for SIMD implementation it is likely more interesting to use the
- * two-loops algorithm variant.
*/
-static void compute_safe_ssd_integral_image_c(uint32_t *dst, int dst_linesize_32,
- const uint8_t *s1, int linesize1,
- const uint8_t *s2, int linesize2,
+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)
{
int x, y;
+ const uint32_t *dst_top = dst - dst_linesize_32;
- for (y = 0; y < h; y++) {
- uint32_t acc = dst[-1] - dst[-dst_linesize_32 - 1];
+ /* SIMD-friendly assumptions allowed here */
+ av_assert2(!(w & 0xf) && w >= 16 && h >= 1);
- for (x = 0; x < w; x++) {
- const int d = s1[x] - s2[x];
- acc += d * d;
- dst[x] = dst[-dst_linesize_32 + x] + acc;
+ for (y = 0; y < h; y++) {
+ for (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;
}
}
* @param w width to compute
* @param h height to compute
*/
-static inline void compute_unsafe_ssd_integral_image(uint32_t *dst, int dst_linesize_32,
+static inline void compute_unsafe_ssd_integral_image(uint32_t *dst, ptrdiff_t dst_linesize_32,
int startx, int starty,
- const uint8_t *src, int linesize,
+ const uint8_t *src, ptrdiff_t linesize,
int offx, int offy, int r, int sw, int sh,
int w, int h)
{
* @param h source height
* @param e research padding edge
*/
-static void compute_ssd_integral_image(uint32_t *ii, int ii_linesize_32,
- const uint8_t *src, int linesize, int offx, int offy,
+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"
// to compare the 2 sources pixels
const int startx_safe = FFMAX(s1x, s2x);
const int starty_safe = FFMAX(s1y, s2y);
- const int endx_safe = FFMIN(s1x + w, s2x + w);
+ 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,
0, starty_safe,
src, linesize,
offx, offy, e, w, h,
- startx_safe, endy_safe - starty_safe);
+ 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);
- compute_safe_ssd_integral_image_c(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,
- endx_safe - startx_safe, endy_safe - starty_safe);
+ 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, endy_safe - starty_safe);
+ 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,
const int e = FFMAX(s->research_hsize, s->research_hsize_uv)
+ FFMAX(s->patch_hsize, s->patch_hsize_uv);
- s->chroma_w = FF_CEIL_RSHIFT(inlink->w, desc->log2_chroma_w);
- s->chroma_h = FF_CEIL_RSHIFT(inlink->h, desc->log2_chroma_h);
+ 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"
struct thread_data {
const uint8_t *src;
- int src_linesize;
+ ptrdiff_t src_linesize;
int startx, starty;
int endx, endy;
const uint32_t *ii_start;
int x, y;
NLMeansContext *s = ctx->priv;
const struct thread_data *td = arg;
- const uint8_t *src = td->src;
- const int src_linesize = td->src_linesize;
+ 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;
for (y = starty; y < endy; y++) {
+ const uint8_t *src = td->src + y*src_linesize;
+ struct weighted_avg *wa = s->wa + y*s->wa_linesize;
for (x = td->startx; x < td->endx; x++) {
- const int patch_diff_sq = get_integral_patch_value(td->ii_start, s->ii_lz_32, x, y, td->p);
+ /*
+ * 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 = ii[x];
+ const uint32_t b = ii[x + dist_b];
+ const uint32_t d = ii[x + dist_d];
+ const uint32_t e = ii[x + dist_e];
+ const uint32_t patch_diff_sq = e - d - b + a;
+
if (patch_diff_sq < s->max_meaningful_diff) {
- struct weighted_avg *wa = &s->wa[y*s->wa_linesize + x];
- const int weight_lut_idx = patch_diff_sq * s->pdiff_lut_scale;
- const double weight = s->weight_lut[weight_lut_idx]; // exp(-patch_diff_sq * s->pdiff_scale)
- wa->total_weight += weight;
- wa->sum += weight * src[y*src_linesize + x];
+ const float weight = s->weight_lut[patch_diff_sq]; // exp(-patch_diff_sq * s->pdiff_scale)
+ wa[x].total_weight += weight;
+ wa[x].sum += weight * src[x];
}
}
+ ii += s->ii_lz_32;
}
return 0;
}
-static int nlmeans_plane(AVFilterContext *ctx, int w, int h, int p, int r,
- uint8_t *dst, int dst_linesize,
- const uint8_t *src, int src_linesize)
+static void weight_averages(uint8_t *dst, ptrdiff_t dst_linesize,
+ const uint8_t *src, ptrdiff_t src_linesize,
+ struct weighted_avg *wa, ptrdiff_t wa_linesize,
+ int w, int h)
{
int x, y;
+
+ for (y = 0; y < h; y++) {
+ for (x = 0; x < w; x++) {
+ // Also weight the centered pixel
+ wa[x].total_weight += 1.f;
+ wa[x].sum += 1.f * src[x];
+ dst[x] = av_clip_uint8(wa[x].sum / wa[x].total_weight);
+ }
+ dst += dst_linesize;
+ src += src_linesize;
+ wa += wa_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)
+{
int offx, offy;
NLMeansContext *s = ctx->priv;
/* patches center points cover the whole research window so the patches
.p = p,
};
- compute_ssd_integral_image(s->ii, s->ii_lz_32,
+ compute_ssd_integral_image(&s->dsp, s->ii, s->ii_lz_32,
src, src_linesize,
offx, offy, e, w, h);
ctx->internal->execute(ctx, nlmeans_slice, &td, NULL,
}
}
}
- for (y = 0; y < h; y++) {
- for (x = 0; x < w; x++) {
- struct weighted_avg *wa = &s->wa[y*s->wa_linesize + x];
- // Also weight the centered pixel
- wa->total_weight += 1.0;
- wa->sum += 1.0 * src[y*src_linesize + x];
+ weight_averages(dst, dst_linesize, src, src_linesize,
+ s->wa, s->wa_linesize, w, h);
- dst[y*dst_linesize + x] = av_clip_uint8(wa->sum / wa->total_weight);
- }
- }
return 0;
}
} \
} while (0)
+void ff_nlmeans_init(NLMeansDSPContext *dsp)
+{
+ dsp->compute_safe_ssd_integral_image = compute_safe_ssd_integral_image_c;
+
+ if (ARCH_AARCH64)
+ ff_nlmeans_init_aarch64(dsp);
+}
+
static av_cold int init(AVFilterContext *ctx)
{
int i;
const double h = s->sigma * 10.;
s->pdiff_scale = 1. / (h * h);
- s->max_meaningful_diff = -log(1/255.) / s->pdiff_scale;
- s->pdiff_lut_scale = 1./s->max_meaningful_diff * WEIGHT_LUT_SIZE;
- av_assert0((s->max_meaningful_diff - 1) * s->pdiff_lut_scale < FF_ARRAY_ELEMS(s->weight_lut));
- for (i = 0; i < WEIGHT_LUT_SIZE; i++)
- s->weight_lut[i] = exp(-i / s->pdiff_lut_scale * s->pdiff_scale);
+ s->max_meaningful_diff = log(255.) / s->pdiff_scale;
+ s->weight_lut = av_calloc(s->max_meaningful_diff, sizeof(*s->weight_lut));
+ if (!s->weight_lut)
+ return AVERROR(ENOMEM);
+ for (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");
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->wa);
}