(SoftFilters) Port of scale2x.c - buggy/broken

gfx/filters/scale2x.c

@@ -0,0 +1,240 @@
+/*  RetroArch - A frontend for libretro.
+ *  Copyright (C) 2010-2014 - Hans-Kristian Arntzen
+ *
+ *  RetroArch 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 Found-
+ *  ation, either version 3 of the License, or (at your option) any later version.
+ *
+ *  RetroArch 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 RetroArch.
+ *  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+// Compile: gcc -o scale2x.so -shared scale2x.c -std=c99 -O3 -Wall -pedantic -fPIC
+
+#include "softfilter.h"
+#include <stdlib.h>
+
+static void scale2x_generic_rgb565(unsigned width, unsigned height,
+      const uint16_t *__restrict__ src, unsigned src_stride,
+      uint16_t * __restrict__ dst, unsigned dst_stride)
+{
+   unsigned x, y;
+   uint16_t *out0 = (uint16_t*)dst;
+   uint16_t *out1 = (uint16_t*)(dst + dst_stride);
+
+   for (y = 0; y < height; ++y)
+   {
+      const int prevline = (y == 0 ? 0 : src_stride);
+      const int nextline = (y == height - 1 ? 0 : src_stride);
+
+      for (x = 0; x < width; ++x)
+      {
+         const uint16_t A = *(src - prevline);
+         const uint16_t B = (x > 0) ? *(src - 1) : *src;
+         const uint16_t C = *src;
+         const uint16_t D = (x < width - 1) ? *(src + 1) : *src;
+         const uint16_t E = *(src++ + nextline);
+
+         if (A != E && B != D)
+         {
+            *out0++ = (A == B ? A : C);
+            *out0++ = (A == D ? A : C);
+            *out1++ = (E == B ? E : C);
+            *out1++ = (E == D ? E : C);
+         }
+         else
+         {
+            *out0++ = C;
+            *out0++ = C;
+            *out1++ = C;
+            *out1++ = C;
+         }
+      }
+
+      src += src_stride - width;
+      out0 += dst_stride + dst_stride - (width << 1);
+      out1 += dst_stride + dst_stride - (width << 1);
+   }
+}
+
+static void scale2x_generic_xrgb8888(unsigned width, unsigned height,
+      const uint32_t *__restrict__ src, unsigned src_stride,
+      uint32_t * __restrict__ dst, unsigned dst_stride)
+{
+   unsigned x, y;
+   uint32_t *out0 = (uint32_t*)dst;
+   uint32_t *out1 = (uint32_t*)(dst + dst_stride);
+
+   for (y = 0; y < height; ++y)
+   {
+      const int prevline = (y == 0 ? 0 : src_stride);
+      const int nextline = (y == height - 1 ? 0 : src_stride);
+
+      for (x = 0; x < width; ++x)
+      {
+         const uint32_t A = *(src - prevline);
+         const uint32_t B = (x > 0) ? *(src - 1) : *src;
+         const uint32_t C = *src;
+         const uint32_t D = (x < width - 1) ? *(src + 1) : *src;
+         const uint32_t E = *(src++ + nextline);
+
+         if (A != E && B != D)
+         {
+            *out0++ = (A == B ? A : C);
+            *out0++ = (A == D ? A : C);
+            *out1++ = (E == B ? E : C);
+            *out1++ = (E == D ? E : C);
+         }
+         else
+         {
+            *out0++ = C;
+            *out0++ = C;
+            *out1++ = C;
+            *out1++ = C;
+         }
+      }
+
+      src += src_stride - width;
+      out0 += dst_stride + dst_stride - (width << 1);
+      out1 += dst_stride + dst_stride - (width << 1);
+   }
+}
+
+static unsigned scale2x_generic_input_fmts(void)
+{
+   return SOFTFILTER_FMT_XRGB8888 | SOFTFILTER_FMT_RGB565;
+}
+
+static unsigned scale2x_generic_output_fmts(unsigned input_fmts)
+{
+   return input_fmts;
+}
+
+struct thread_data
+{
+   uint32_t *out_data;
+   const uint32_t *in_data;
+   size_t out_pitch;
+   size_t in_pitch;
+   unsigned width;
+   unsigned height;
+};
+
+struct filter_data
+{
+   unsigned threads;
+   struct thread_data *workers;
+   unsigned in_fmt;
+};
+
+static unsigned scale2x_generic_threads(void *data)
+{
+   struct filter_data *filt = (struct filter_data*)data;
+   return filt->threads;;
+}
+
+static void *scale2x_generic_create(unsigned in_fmt, unsigned out_fmt,
+      unsigned max_width, unsigned max_height,
+      unsigned threads, softfilter_simd_mask_t simd)
+{
+   (void)simd;
+
+   struct filter_data *filt = (struct filter_data*)calloc(1, sizeof(*filt));
+   if (!filt)
+      return NULL;
+   filt->workers = calloc(threads, sizeof(struct thread_data));
+   filt->threads = threads;
+   filt->in_fmt  = in_fmt;
+   if (!filt->workers)
+   {
+      free(filt);
+      return NULL;
+   }
+   return filt;
+}
+
+static void scale2x_generic_output(void *data, unsigned *out_width, unsigned *out_height,
+      unsigned width, unsigned height)
+{
+   *out_width = width * 2;
+   *out_height = height * 2;
+}
+
+static void scale2x_generic_destroy(void *data)
+{
+   struct filter_data *filt = (struct filter_data*)data;
+   free(filt->workers);
+   free(filt);
+}
+
+static void work_cb_xrgb8888(void *data, void *thread_data)
+{
+   struct thread_data *thr = (struct thread_data*)thread_data;
+   const uint32_t *input = (const uint32_t*)thr->in_data;
+   uint32_t *output = (uint32_t*)thr->out_data;
+   unsigned width = thr->width;
+   unsigned height = thr->height;
+
+   scale2x_generic_xrgb8888(width, height, input, thr->in_pitch, output, thr->out_pitch);
+}
+
+static void work_cb_rgb565(void *data, void *thread_data)
+{
+   struct thread_data *thr = (struct thread_data*)thread_data;
+   const uint16_t *input = (const uint16_t*)thr->in_data;
+   uint16_t *output = (uint16_t*)thr->out_data;
+   unsigned width = thr->width;
+   unsigned height = thr->height;
+
+   scale2x_generic_rgb565(width, height, input, thr->in_pitch, output, thr->out_pitch);
+}
+
+static void scale2x_generic_packets(void *data,
+      struct softfilter_work_packet *packets,
+      void *output, size_t output_stride,
+      const void *input, unsigned width, unsigned height, size_t input_stride)
+{
+   struct filter_data *filt = (struct filter_data*)data;
+   for (unsigned i = 0; i < filt->threads; i++)
+   {
+      struct thread_data *thr = (struct thread_data*)&filt->workers[i];
+      unsigned y_start = (height * i) / filt->threads;
+      unsigned y_end = (height * (i + 1)) / filt->threads;
+      thr->out_data = (uint32_t*)output + y_start * (output_stride >> 2);
+      thr->in_data = (const uint32_t*)input + y_start * (input_stride >> 2);
+      thr->out_pitch = output_stride;
+      thr->in_pitch = input_stride;
+      thr->width = width;
+      thr->height = y_end - y_start;
+
+      if (filt->in_fmt == SOFTFILTER_FMT_XRGB8888)
+         packets[i].work = work_cb_xrgb8888;
+      else if (filt->in_fmt == SOFTFILTER_FMT_RGB565)
+         packets[i].work = work_cb_rgb565;
+      packets[i].thread_data = thr;
+   }
+}
+
+static const struct softfilter_implementation scale2x_generic = {
+   scale2x_generic_input_fmts,
+   scale2x_generic_output_fmts,
+
+   scale2x_generic_create,
+   scale2x_generic_destroy,
+
+   scale2x_generic_threads,
+   scale2x_generic_output,
+   scale2x_generic_packets,
+   "Scale2x",
+   SOFTFILTER_API_VERSION,
+};
+
+const struct softfilter_implementation *softfilter_get_implementation(softfilter_simd_mask_t simd)
+{
+   (void)simd;
+   return &scale2x_generic;
+}