libavfilter/vf_gradfun.c
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00001 /*
00002  * Copyright (c) 2010 Nolan Lum <nol888@gmail.com>
00003  * Copyright (c) 2009 Loren Merritt <lorenm@u.washignton.edu>
00004  *
00005  * This file is part of Libav.
00006  *
00007  * Libav is free software; you can redistribute it and/or
00008  * modify it under the terms of the GNU Lesser General Public
00009  * License as published by the Free Software Foundation; either
00010  * version 2.1 of the License, or (at your option) any later version.
00011  *
00012  * Libav is distributed in the hope that it will be useful,
00013  * but WITHOUT ANY WARRANTY; without even the implied warranty of
00014  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
00015  * Lesser General Public License for more details.
00016  *
00017  * You should have received a copy of the GNU Lesser General Public
00018  * License along with Libav; if not, write to the Free Software
00019  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
00020  */
00021 
00035 #include "libavutil/imgutils.h"
00036 #include "libavutil/cpu.h"
00037 #include "libavutil/pixdesc.h"
00038 #include "avfilter.h"
00039 #include "gradfun.h"
00040 
00041 DECLARE_ALIGNED(16, static const uint16_t, dither)[8][8] = {
00042     {0x00,0x60,0x18,0x78,0x06,0x66,0x1E,0x7E},
00043     {0x40,0x20,0x58,0x38,0x46,0x26,0x5E,0x3E},
00044     {0x10,0x70,0x08,0x68,0x16,0x76,0x0E,0x6E},
00045     {0x50,0x30,0x48,0x28,0x56,0x36,0x4E,0x2E},
00046     {0x04,0x64,0x1C,0x7C,0x02,0x62,0x1A,0x7A},
00047     {0x44,0x24,0x5C,0x3C,0x42,0x22,0x5A,0x3A},
00048     {0x14,0x74,0x0C,0x6C,0x12,0x72,0x0A,0x6A},
00049     {0x54,0x34,0x4C,0x2C,0x52,0x32,0x4A,0x2A},
00050 };
00051 
00052 void ff_gradfun_filter_line_c(uint8_t *dst, uint8_t *src, uint16_t *dc, int width, int thresh, const uint16_t *dithers)
00053 {
00054     int x;
00055     for (x = 0; x < width; x++, dc += x & 1) {
00056         int pix = src[x] << 7;
00057         int delta = dc[0] - pix;
00058         int m = abs(delta) * thresh >> 16;
00059         m = FFMAX(0, 127 - m);
00060         m = m * m * delta >> 14;
00061         pix += m + dithers[x & 7];
00062         dst[x] = av_clip_uint8(pix >> 7);
00063     }
00064 }
00065 
00066 void ff_gradfun_blur_line_c(uint16_t *dc, uint16_t *buf, uint16_t *buf1, uint8_t *src, int src_linesize, int width)
00067 {
00068     int x, v, old;
00069     for (x = 0; x < width; x++) {
00070         v = buf1[x] + src[2 * x] + src[2 * x + 1] + src[2 * x + src_linesize] + src[2 * x + 1 + src_linesize];
00071         old = buf[x];
00072         buf[x] = v;
00073         dc[x] = v - old;
00074     }
00075 }
00076 
00077 static void filter(GradFunContext *ctx, uint8_t *dst, uint8_t *src, int width, int height, int dst_linesize, int src_linesize, int r)
00078 {
00079     int bstride = FFALIGN(width, 16) / 2;
00080     int y;
00081     uint32_t dc_factor = (1 << 21) / (r * r);
00082     uint16_t *dc = ctx->buf + 16;
00083     uint16_t *buf = ctx->buf + bstride + 32;
00084     int thresh = ctx->thresh;
00085 
00086     memset(dc, 0, (bstride + 16) * sizeof(*buf));
00087     for (y = 0; y < r; y++)
00088         ctx->blur_line(dc, buf + y * bstride, buf + (y - 1) * bstride, src + 2 * y * src_linesize, src_linesize, width / 2);
00089     for (;;) {
00090         if (y < height - r) {
00091             int mod = ((y + r) / 2) % r;
00092             uint16_t *buf0 = buf + mod * bstride;
00093             uint16_t *buf1 = buf + (mod ? mod - 1 : r - 1) * bstride;
00094             int x, v;
00095             ctx->blur_line(dc, buf0, buf1, src + (y + r) * src_linesize, src_linesize, width / 2);
00096             for (x = v = 0; x < r; x++)
00097                 v += dc[x];
00098             for (; x < width / 2; x++) {
00099                 v += dc[x] - dc[x-r];
00100                 dc[x-r] = v * dc_factor >> 16;
00101             }
00102             for (; x < (width + r + 1) / 2; x++)
00103                 dc[x-r] = v * dc_factor >> 16;
00104             for (x = -r / 2; x < 0; x++)
00105                 dc[x] = dc[0];
00106         }
00107         if (y == r) {
00108             for (y = 0; y < r; y++)
00109                 ctx->filter_line(dst + y * dst_linesize, src + y * src_linesize, dc - r / 2, width, thresh, dither[y & 7]);
00110         }
00111         ctx->filter_line(dst + y * dst_linesize, src + y * src_linesize, dc - r / 2, width, thresh, dither[y & 7]);
00112         if (++y >= height) break;
00113         ctx->filter_line(dst + y * dst_linesize, src + y * src_linesize, dc - r / 2, width, thresh, dither[y & 7]);
00114         if (++y >= height) break;
00115     }
00116 }
00117 
00118 static av_cold int init(AVFilterContext *ctx, const char *args, void *opaque)
00119 {
00120     GradFunContext *gf = ctx->priv;
00121     float thresh = 1.2;
00122     int radius = 16;
00123     av_unused int cpu_flags = av_get_cpu_flags();
00124 
00125     if (args)
00126         sscanf(args, "%f:%d", &thresh, &radius);
00127 
00128     thresh = av_clipf(thresh, 0.51, 255);
00129     gf->thresh = (1 << 15) / thresh;
00130     gf->radius = av_clip((radius + 1) & ~1, 4, 32);
00131 
00132     gf->blur_line = ff_gradfun_blur_line_c;
00133     gf->filter_line = ff_gradfun_filter_line_c;
00134 
00135     if (HAVE_MMX && cpu_flags & AV_CPU_FLAG_MMX2)
00136         gf->filter_line = ff_gradfun_filter_line_mmx2;
00137     if (HAVE_SSSE3 && cpu_flags & AV_CPU_FLAG_SSSE3)
00138         gf->filter_line = ff_gradfun_filter_line_ssse3;
00139     if (HAVE_SSE && cpu_flags & AV_CPU_FLAG_SSE2)
00140         gf->blur_line = ff_gradfun_blur_line_sse2;
00141 
00142     av_log(ctx, AV_LOG_INFO, "threshold:%.2f radius:%d\n", thresh, gf->radius);
00143 
00144     return 0;
00145 }
00146 
00147 static av_cold void uninit(AVFilterContext *ctx)
00148 {
00149     GradFunContext *gf = ctx->priv;
00150     av_freep(&gf->buf);
00151 }
00152 
00153 static int query_formats(AVFilterContext *ctx)
00154 {
00155     static const enum PixelFormat pix_fmts[] = {
00156         PIX_FMT_YUV410P,            PIX_FMT_YUV420P,
00157         PIX_FMT_GRAY8,              PIX_FMT_NV12,
00158         PIX_FMT_NV21,               PIX_FMT_YUV444P,
00159         PIX_FMT_YUV422P,            PIX_FMT_YUV411P,
00160         PIX_FMT_NONE
00161     };
00162 
00163     avfilter_set_common_formats(ctx, avfilter_make_format_list(pix_fmts));
00164 
00165     return 0;
00166 }
00167 
00168 static int config_input(AVFilterLink *inlink)
00169 {
00170     GradFunContext *gf = inlink->dst->priv;
00171     int hsub = av_pix_fmt_descriptors[inlink->format].log2_chroma_w;
00172     int vsub = av_pix_fmt_descriptors[inlink->format].log2_chroma_h;
00173 
00174     gf->buf = av_mallocz((FFALIGN(inlink->w, 16) * (gf->radius + 1) / 2 + 32) * sizeof(uint16_t));
00175     if (!gf->buf)
00176         return AVERROR(ENOMEM);
00177 
00178     gf->chroma_w = -((-inlink->w) >> hsub);
00179     gf->chroma_h = -((-inlink->h) >> vsub);
00180     gf->chroma_r = av_clip(((((gf->radius >> hsub) + (gf->radius >> vsub)) / 2 ) + 1) & ~1, 4, 32);
00181 
00182     return 0;
00183 }
00184 
00185 static void start_frame(AVFilterLink *inlink, AVFilterBufferRef *inpicref)
00186 {
00187     AVFilterLink *outlink = inlink->dst->outputs[0];
00188     AVFilterBufferRef *outpicref;
00189 
00190     if (inpicref->perms & AV_PERM_PRESERVE) {
00191         outpicref = avfilter_get_video_buffer(outlink, AV_PERM_WRITE, outlink->w, outlink->h);
00192         avfilter_copy_buffer_ref_props(outpicref, inpicref);
00193         outpicref->video->w = outlink->w;
00194         outpicref->video->h = outlink->h;
00195     } else
00196         outpicref = inpicref;
00197 
00198     outlink->out_buf = outpicref;
00199     avfilter_start_frame(outlink, avfilter_ref_buffer(outpicref, ~0));
00200 }
00201 
00202 static void null_draw_slice(AVFilterLink *link, int y, int h, int slice_dir) { }
00203 
00204 static void end_frame(AVFilterLink *inlink)
00205 {
00206     GradFunContext *gf = inlink->dst->priv;
00207     AVFilterBufferRef *inpic = inlink->cur_buf;
00208     AVFilterLink *outlink = inlink->dst->outputs[0];
00209     AVFilterBufferRef *outpic = outlink->out_buf;
00210     int p;
00211 
00212     for (p = 0; p < 4 && inpic->data[p]; p++) {
00213         int w = inlink->w;
00214         int h = inlink->h;
00215         int r = gf->radius;
00216         if (p) {
00217             w = gf->chroma_w;
00218             h = gf->chroma_h;
00219             r = gf->chroma_r;
00220         }
00221 
00222         if (FFMIN(w, h) > 2 * r)
00223             filter(gf, outpic->data[p], inpic->data[p], w, h, outpic->linesize[p], inpic->linesize[p], r);
00224         else if (outpic->data[p] != inpic->data[p])
00225             av_image_copy_plane(outpic->data[p], outpic->linesize[p], inpic->data[p], inpic->linesize[p], w, h);
00226     }
00227 
00228     avfilter_draw_slice(outlink, 0, inlink->h, 1);
00229     avfilter_end_frame(outlink);
00230     avfilter_unref_buffer(inpic);
00231     if (outpic != inpic)
00232         avfilter_unref_buffer(outpic);
00233 }
00234 
00235 AVFilter avfilter_vf_gradfun = {
00236     .name          = "gradfun",
00237     .description   = NULL_IF_CONFIG_SMALL("Debands video quickly using gradients."),
00238     .priv_size     = sizeof(GradFunContext),
00239     .init          = init,
00240     .uninit        = uninit,
00241     .query_formats = query_formats,
00242 
00243     .inputs    = (AVFilterPad[]) {{ .name             = "default",
00244                                     .type             = AVMEDIA_TYPE_VIDEO,
00245                                     .config_props     = config_input,
00246                                     .start_frame      = start_frame,
00247                                     .draw_slice       = null_draw_slice,
00248                                     .end_frame        = end_frame,
00249                                     .min_perms        = AV_PERM_READ, },
00250                                   { .name = NULL}},
00251     .outputs   = (AVFilterPad[]) {{ .name             = "default",
00252                                     .type             = AVMEDIA_TYPE_VIDEO, },
00253                                   { .name = NULL}},
00254 };