libavfilter/vf_super2xsai.c
b7a7830d
 /*
  * Copyright (c) 2010 Niel van der Westhuizen <nielkie@gmail.com>
  * Copyright (c) 2002 A'rpi
  * Copyright (c) 1997-2001 ZSNES Team ( zsknight@zsnes.com / _demo_@zsnes.com )
  *
  * This file is part of FFmpeg.
  *
  * FFmpeg is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
  * the Free Software Foundation; either version 2 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 General Public License for more details.
  *
  * You should have received a copy of the GNU 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.
  */
 
 /**
  * @file
  * Super 2xSaI video filter
  * Ported from MPlayer libmpcodecs/vf_2xsai.c.
  */
 
 #include "libavutil/pixdesc.h"
 #include "libavutil/intreadwrite.h"
 #include "avfilter.h"
 
 typedef struct {
     /* masks used for two pixels interpolation */
     uint32_t hi_pixel_mask;
     uint32_t lo_pixel_mask;
 
     /* masks used for four pixels interpolation */
     uint32_t q_hi_pixel_mask;
     uint32_t q_lo_pixel_mask;
 
     int bpp; ///< bytes per pixel, pixel stride for each (packed) pixel
 } Super2xSaIContext;
 
 #define GET_RESULT(A, B, C, D) ((A != C || A != D) - (B != C || B != D))
 
 #define INTERPOLATE(A, B) (((A & hi_pixel_mask) >> 1) + ((B & hi_pixel_mask) >> 1) + (A & B & lo_pixel_mask))
 
 #define Q_INTERPOLATE(A, B, C, D) ((A & q_hi_pixel_mask) >> 2) + ((B & q_hi_pixel_mask) >> 2) + ((C & q_hi_pixel_mask) >> 2) + ((D & q_hi_pixel_mask) >> 2) \
     + ((((A & q_lo_pixel_mask) + (B & q_lo_pixel_mask) + (C & q_lo_pixel_mask) + (D & q_lo_pixel_mask)) >> 2) & q_lo_pixel_mask)
 
 static void super2xsai(AVFilterContext *ctx,
                        uint8_t *src, int src_linesize,
                        uint8_t *dst, int dst_linesize,
                        int width, int height)
 {
     Super2xSaIContext *sai = ctx->priv;
     unsigned int x, y;
     uint32_t color[4][4];
     unsigned char *src_line[4];
     const int bpp = sai->bpp;
     const uint32_t hi_pixel_mask = sai->hi_pixel_mask;
     const uint32_t lo_pixel_mask = sai->lo_pixel_mask;
     const uint32_t q_hi_pixel_mask = sai->q_hi_pixel_mask;
     const uint32_t q_lo_pixel_mask = sai->q_lo_pixel_mask;
 
     /* Point to the first 4 lines, first line is duplicated */
     src_line[0] = src;
     src_line[1] = src;
     src_line[2] = src + src_linesize*FFMIN(1, height-1);
     src_line[3] = src + src_linesize*FFMIN(2, height-1);
 
 #define READ_COLOR4(dst, src_line, off) dst = *((const uint32_t *)src_line + off)
 #define READ_COLOR3(dst, src_line, off) dst = AV_RL24 (src_line + 3*off)
 #define READ_COLOR2(dst, src_line, off) dst = *((const uint16_t *)src_line + off)
 
     /* Initialise the color matrix for this row. */
     switch (bpp) {
     case 4:
         READ_COLOR4(color[0][0], src_line[0], 0); color[0][1] = color[0][0]; READ_COLOR4(color[0][2], src_line[0], 1); READ_COLOR4(color[0][3], src_line[0], 2);
         READ_COLOR4(color[1][0], src_line[1], 0); color[1][1] = color[1][0]; READ_COLOR4(color[1][2], src_line[1], 1); READ_COLOR4(color[1][3], src_line[1], 2);
         READ_COLOR4(color[2][0], src_line[2], 0); color[2][1] = color[2][0]; READ_COLOR4(color[2][2], src_line[2], 1); READ_COLOR4(color[2][3], src_line[2], 2);
         READ_COLOR4(color[3][0], src_line[3], 0); color[3][1] = color[3][0]; READ_COLOR4(color[3][2], src_line[3], 1); READ_COLOR4(color[3][3], src_line[3], 2);
         break;
     case 3:
         READ_COLOR3(color[0][0], src_line[0], 0); color[0][1] = color[0][0]; READ_COLOR3(color[0][2], src_line[0], 1); READ_COLOR3(color[0][3], src_line[0], 2);
         READ_COLOR3(color[1][0], src_line[1], 0); color[1][1] = color[1][0]; READ_COLOR3(color[1][2], src_line[1], 1); READ_COLOR3(color[1][3], src_line[1], 2);
         READ_COLOR3(color[2][0], src_line[2], 0); color[2][1] = color[2][0]; READ_COLOR3(color[2][2], src_line[2], 1); READ_COLOR3(color[2][3], src_line[2], 2);
         READ_COLOR3(color[3][0], src_line[3], 0); color[3][1] = color[3][0]; READ_COLOR3(color[3][2], src_line[3], 1); READ_COLOR3(color[3][3], src_line[3], 2);
         break;
     default:
         READ_COLOR2(color[0][0], src_line[0], 0); color[0][1] = color[0][0]; READ_COLOR2(color[0][2], src_line[0], 1); READ_COLOR2(color[0][3], src_line[0], 2);
         READ_COLOR2(color[1][0], src_line[1], 0); color[1][1] = color[1][0]; READ_COLOR2(color[1][2], src_line[1], 1); READ_COLOR2(color[1][3], src_line[1], 2);
         READ_COLOR2(color[2][0], src_line[2], 0); color[2][1] = color[2][0]; READ_COLOR2(color[2][2], src_line[2], 1); READ_COLOR2(color[2][3], src_line[2], 2);
         READ_COLOR2(color[3][0], src_line[3], 0); color[3][1] = color[3][0]; READ_COLOR2(color[3][2], src_line[3], 1); READ_COLOR2(color[3][3], src_line[3], 2);
     }
 
     for (y = 0; y < height; y++) {
         uint8_t *dst_line[2];
 
         dst_line[0] = dst + dst_linesize*2*y;
         dst_line[1] = dst + dst_linesize*(2*y+1);
 
         for (x = 0; x < width; x++) {
             uint32_t product1a, product1b, product2a, product2b;
 
 //---------------------------------------  B0 B1 B2 B3    0  1  2  3
 //                                         4  5* 6  S2 -> 4  5* 6  7
 //                                         1  2  3  S1    8  9 10 11
 //                                         A0 A1 A2 A3   12 13 14 15
 //--------------------------------------
             if (color[2][1] == color[1][2] && color[1][1] != color[2][2]) {
                 product2b = color[2][1];
                 product1b = product2b;
             } else if (color[1][1] == color[2][2] && color[2][1] != color[1][2]) {
                 product2b = color[1][1];
                 product1b = product2b;
             } else if (color[1][1] == color[2][2] && color[2][1] == color[1][2]) {
                 int r = 0;
 
                 r += GET_RESULT(color[1][2], color[1][1], color[1][0], color[3][1]);
                 r += GET_RESULT(color[1][2], color[1][1], color[2][0], color[0][1]);
                 r += GET_RESULT(color[1][2], color[1][1], color[3][2], color[2][3]);
                 r += GET_RESULT(color[1][2], color[1][1], color[0][2], color[1][3]);
 
                 if (r > 0)
                     product1b = color[1][2];
                 else if (r < 0)
                     product1b = color[1][1];
                 else
                     product1b = INTERPOLATE(color[1][1], color[1][2]);
 
                 product2b = product1b;
             } else {
                 if (color[1][2] == color[2][2] && color[2][2] == color[3][1] && color[2][1] != color[3][2] && color[2][2] != color[3][0])
                     product2b = Q_INTERPOLATE(color[2][2], color[2][2], color[2][2], color[2][1]);
                 else if (color[1][1] == color[2][1] && color[2][1] == color[3][2] && color[3][1] != color[2][2] && color[2][1] != color[3][3])
                     product2b = Q_INTERPOLATE(color[2][1], color[2][1], color[2][1], color[2][2]);
                 else
                     product2b = INTERPOLATE(color[2][1], color[2][2]);
 
                 if (color[1][2] == color[2][2] && color[1][2] == color[0][1] && color[1][1] != color[0][2] && color[1][2] != color[0][0])
                     product1b = Q_INTERPOLATE(color[1][2], color[1][2], color[1][2], color[1][1]);
                 else if (color[1][1] == color[2][1] && color[1][1] == color[0][2] && color[0][1] != color[1][2] && color[1][1] != color[0][3])
                     product1b = Q_INTERPOLATE(color[1][2], color[1][1], color[1][1], color[1][1]);
                 else
                     product1b = INTERPOLATE(color[1][1], color[1][2]);
             }
 
             if (color[1][1] == color[2][2] && color[2][1] != color[1][2] && color[1][0] == color[1][1] && color[1][1] != color[3][2])
                 product2a = INTERPOLATE(color[2][1], color[1][1]);
             else if (color[1][1] == color[2][0] && color[1][2] == color[1][1] && color[1][0] != color[2][1] && color[1][1] != color[3][0])
                 product2a = INTERPOLATE(color[2][1], color[1][1]);
             else
                 product2a = color[2][1];
 
             if (color[2][1] == color[1][2] && color[1][1] != color[2][2] && color[2][0] == color[2][1] && color[2][1] != color[0][2])
                 product1a = INTERPOLATE(color[2][1], color[1][1]);
             else if (color[1][0] == color[2][1] && color[2][2] == color[2][1] && color[2][0] != color[1][1] && color[2][1] != color[0][0])
                 product1a = INTERPOLATE(color[2][1], color[1][1]);
             else
                 product1a = color[1][1];
 
             /* Set the calculated pixels */
             switch (bpp) {
             case 4:
                 AV_WN32A(dst_line[0] + x * 8,     product1a);
                 AV_WN32A(dst_line[0] + x * 8 + 4, product1b);
                 AV_WN32A(dst_line[1] + x * 8,     product2a);
                 AV_WN32A(dst_line[1] + x * 8 + 4, product2b);
                 break;
             case 3:
                 AV_WL24(dst_line[0] + x * 6,     product1a);
                 AV_WL24(dst_line[0] + x * 6 + 3, product1b);
                 AV_WL24(dst_line[1] + x * 6,     product2a);
                 AV_WL24(dst_line[1] + x * 6 + 3, product2b);
                 break;
             default: // bpp = 2
                 AV_WN32A(dst_line[0] + x * 4, product1a | (product1b << 16));
                 AV_WN32A(dst_line[1] + x * 4, product2a | (product2b << 16));
             }
 
             /* Move color matrix forward */
             color[0][0] = color[0][1]; color[0][1] = color[0][2]; color[0][2] = color[0][3];
             color[1][0] = color[1][1]; color[1][1] = color[1][2]; color[1][2] = color[1][3];
             color[2][0] = color[2][1]; color[2][1] = color[2][2]; color[2][2] = color[2][3];
             color[3][0] = color[3][1]; color[3][1] = color[3][2]; color[3][2] = color[3][3];
 
             if (x < width - 3) {
                 x += 3;
                 switch (bpp) {
                 case 4:
                     READ_COLOR4(color[0][3], src_line[0], x);
                     READ_COLOR4(color[1][3], src_line[1], x);
                     READ_COLOR4(color[2][3], src_line[2], x);
                     READ_COLOR4(color[3][3], src_line[3], x);
                     break;
                 case 3:
                     READ_COLOR3(color[0][3], src_line[0], x);
                     READ_COLOR3(color[1][3], src_line[1], x);
                     READ_COLOR3(color[2][3], src_line[2], x);
                     READ_COLOR3(color[3][3], src_line[3], x);
                     break;
                 default:        /* case 2 */
                     READ_COLOR2(color[0][3], src_line[0], x);
                     READ_COLOR2(color[1][3], src_line[1], x);
                     READ_COLOR2(color[2][3], src_line[2], x);
                     READ_COLOR2(color[3][3], src_line[3], x);
                 }
                 x -= 3;
             }
         }
 
         /* We're done with one line, so we shift the source lines up */
         src_line[0] = src_line[1];
         src_line[1] = src_line[2];
         src_line[2] = src_line[3];
 
         /* Read next line */
         src_line[3] = src_line[2];
         if (y < height - 3)
             src_line[3] += src_linesize;
 
         switch (bpp) {
         case 4:
             READ_COLOR4(color[0][0], src_line[0], 0); color[0][1] = color[0][0]; READ_COLOR4(color[0][2], src_line[0], 1); READ_COLOR4(color[0][3], src_line[0], 2);
             READ_COLOR4(color[1][0], src_line[1], 0); color[1][1] = color[1][0]; READ_COLOR4(color[1][2], src_line[1], 1); READ_COLOR4(color[1][3], src_line[1], 2);
             READ_COLOR4(color[2][0], src_line[2], 0); color[2][1] = color[2][1]; READ_COLOR4(color[2][2], src_line[2], 1); READ_COLOR4(color[2][3], src_line[2], 2);
             READ_COLOR4(color[3][0], src_line[3], 0); color[3][1] = color[3][0]; READ_COLOR4(color[3][2], src_line[3], 1); READ_COLOR4(color[3][3], src_line[3], 2);
             break;
         case 3:
             READ_COLOR3(color[0][0], src_line[0], 0); color[0][1] = color[0][0]; READ_COLOR3(color[0][2], src_line[0], 1); READ_COLOR3(color[0][3], src_line[0], 2);
             READ_COLOR3(color[1][0], src_line[1], 0); color[1][1] = color[1][0]; READ_COLOR3(color[1][2], src_line[1], 1); READ_COLOR3(color[1][3], src_line[1], 2);
             READ_COLOR3(color[2][0], src_line[2], 0); color[2][1] = color[2][1]; READ_COLOR3(color[2][2], src_line[2], 1); READ_COLOR3(color[2][3], src_line[2], 2);
             READ_COLOR3(color[3][0], src_line[3], 0); color[3][1] = color[3][0]; READ_COLOR3(color[3][2], src_line[3], 1); READ_COLOR3(color[3][3], src_line[3], 2);
             break;
         default:
             READ_COLOR2(color[0][0], src_line[0], 0); color[0][1] = color[0][0]; READ_COLOR2(color[0][2], src_line[0], 1); READ_COLOR2(color[0][3], src_line[0], 2);
             READ_COLOR2(color[1][0], src_line[1], 0); color[1][1] = color[1][0]; READ_COLOR2(color[1][2], src_line[1], 1); READ_COLOR2(color[1][3], src_line[1], 2);
             READ_COLOR2(color[2][0], src_line[2], 0); color[2][1] = color[2][1]; READ_COLOR2(color[2][2], src_line[2], 1); READ_COLOR2(color[2][3], src_line[2], 2);
             READ_COLOR2(color[3][0], src_line[3], 0); color[3][1] = color[3][0]; READ_COLOR2(color[3][2], src_line[3], 1); READ_COLOR2(color[3][3], src_line[3], 2);
         }
     } // y loop
 }
 
 static int query_formats(AVFilterContext *ctx)
 {
     static const enum PixelFormat pix_fmts[] = {
         PIX_FMT_RGBA, PIX_FMT_BGRA, PIX_FMT_ARGB, PIX_FMT_ABGR,
         PIX_FMT_RGB24, PIX_FMT_BGR24,
         PIX_FMT_RGB565, PIX_FMT_BGR565, PIX_FMT_RGB555, PIX_FMT_BGR555,
         PIX_FMT_NONE
     };
 
     avfilter_set_common_pixel_formats(ctx, avfilter_make_format_list(pix_fmts));
     return 0;
 }
 
 static int config_input(AVFilterLink *inlink)
 {
     Super2xSaIContext *sai = inlink->dst->priv;
 
     sai->hi_pixel_mask   = 0xFEFEFEFE;
     sai->lo_pixel_mask   = 0x01010101;
     sai->q_hi_pixel_mask = 0xFCFCFCFC;
     sai->q_lo_pixel_mask = 0x03030303;
     sai->bpp  = 4;
 
     switch (inlink->format) {
     case PIX_FMT_RGB24:
     case PIX_FMT_BGR24:
         sai->bpp = 3;
         break;
 
     case PIX_FMT_RGB565:
     case PIX_FMT_BGR565:
         sai->hi_pixel_mask   = 0xF7DEF7DE;
         sai->lo_pixel_mask   = 0x08210821;
         sai->q_hi_pixel_mask = 0xE79CE79C;
         sai->q_lo_pixel_mask = 0x18631863;
         sai->bpp = 2;
         break;
 
     case PIX_FMT_BGR555:
     case PIX_FMT_RGB555:
         sai->hi_pixel_mask   = 0x7BDE7BDE;
         sai->lo_pixel_mask   = 0x04210421;
         sai->q_hi_pixel_mask = 0x739C739C;
         sai->q_lo_pixel_mask = 0x0C630C63;
         sai->bpp = 2;
         break;
     }
 
     return 0;
 }
 
 static int config_output(AVFilterLink *outlink)
 {
     AVFilterLink *inlink = outlink->src->inputs[0];
 
     outlink->w = inlink->w*2;
     outlink->h = inlink->h*2;
 
     av_log(inlink->dst, AV_LOG_INFO, "fmt:%s size:%dx%d -> size:%dx%d\n",
            av_get_pix_fmt_name(inlink->format),
            inlink->w, inlink->h, outlink->w, outlink->h);
 
     return 0;
 }
 
 static void null_draw_slice(AVFilterLink *inlink, int y, int h, int slice_dir) { }
 
 static void end_frame(AVFilterLink *inlink)
 {
     AVFilterLink *outlink = inlink->dst->outputs[0];
     AVFilterBufferRef  *inpicref =  inlink->cur_buf;
     AVFilterBufferRef *outpicref = outlink->out_buf;
 
     super2xsai(inlink->dst, inpicref->data[0], inpicref->linesize[0],
                outpicref->data[0], outpicref->linesize[0],
                inlink->w, inlink->h);
 
     avfilter_unref_buffer(inpicref);
     avfilter_draw_slice(outlink, 0, outlink->h, 1);
     avfilter_end_frame(outlink);
     avfilter_unref_buffer(outpicref);
 }
 
 AVFilter avfilter_vf_super2xsai = {
     .name        = "super2xsai",
     .description = NULL_IF_CONFIG_SMALL("Scale the input by 2x using the Super2xSaI pixel art algorithm."),
     .priv_size   = sizeof(Super2xSaIContext),
     .query_formats = query_formats,
 
     .inputs = (const AVFilterPad[]) {
         { .name             = "default",
           .type             = AVMEDIA_TYPE_VIDEO,
           .config_props     = config_input,
           .draw_slice       = null_draw_slice,
           .end_frame        = end_frame,
           .min_perms        = AV_PERM_READ },
         { .name = NULL }
     },
     .outputs = (const AVFilterPad[]) {
         { .name             = "default",
           .type             = AVMEDIA_TYPE_VIDEO,
           .config_props     = config_output },
         { .name = NULL }
     },
 };