Merge "Move ARGB->YUV functions from dec/vp8l.c to dsp/yuv.c"

src/dec/vp8l.c

@@ -19,6 +19,7 @@
 #include "../dsp/dsp.h"
 #include "../dsp/lossless.h"
 #include "../dsp/yuv.h"
+#include "../utils/endian_inl.h"
 #include "../utils/huffman.h"
 #include "../utils/utils.h"
 
@@ -504,67 +505,29 @@ static int EmitRows(WEBP_CSP_MODE colorspace,
 //------------------------------------------------------------------------------
 // Export to YUVA
 
-// TODO(skal): should be in yuv.c
 static void ConvertToYUVA(const uint32_t* const src, int width, int y_pos,
                           const WebPDecBuffer* const output) {
   const WebPYUVABuffer* const buf = &output->u.YUVA;
+
   // first, the luma plane
-  {
+  WebPConvertARGBToY(src, buf->y + y_pos * buf->y_stride, width);
-    int i;
-    uint8_t* const y = buf->y + y_pos * buf->y_stride;
-    for (i = 0; i < width; ++i) {
-      const uint32_t p = src[i];
-      y[i] = VP8RGBToY((p >> 16) & 0xff, (p >> 8) & 0xff, (p >> 0) & 0xff,
-                       YUV_HALF);
-    }
-  }
 
   // then U/V planes
   {
     uint8_t* const u = buf->u + (y_pos >> 1) * buf->u_stride;
     uint8_t* const v = buf->v + (y_pos >> 1) * buf->v_stride;
-    const int uv_width = width >> 1;
+    // even lines: store values
-    int i;
+    // odd lines: average with previous values
-    for (i = 0; i < uv_width; ++i) {
+    WebPConvertARGBToUV(src, u, v, width, !(y_pos & 1));
-      const uint32_t v0 = src[2 * i + 0];
-      const uint32_t v1 = src[2 * i + 1];
-      // VP8RGBToU/V expects four accumulated pixels. Hence we need to
-      // scale r/g/b value by a factor 2. We just shift v0/v1 one bit less.
-      const int r = ((v0 >> 15) & 0x1fe) + ((v1 >> 15) & 0x1fe);
-      const int g = ((v0 >>  7) & 0x1fe) + ((v1 >>  7) & 0x1fe);
-      const int b = ((v0 <<  1) & 0x1fe) + ((v1 <<  1) & 0x1fe);
-      if (!(y_pos & 1)) {  // even lines: store values
-        u[i] = VP8RGBToU(r, g, b, YUV_HALF << 2);
-        v[i] = VP8RGBToV(r, g, b, YUV_HALF << 2);
-      } else {             // odd lines: average with previous values
-        const int tmp_u = VP8RGBToU(r, g, b, YUV_HALF << 2);
-        const int tmp_v = VP8RGBToV(r, g, b, YUV_HALF << 2);
-        // Approximated average-of-four. But it's an acceptable diff.
-        u[i] = (u[i] + tmp_u + 1) >> 1;
-        v[i] = (v[i] + tmp_v + 1) >> 1;
-      }
-    }
-    if (width & 1) {       // last pixel
-      const uint32_t v0 = src[2 * i + 0];
-      const int r = (v0 >> 14) & 0x3fc;
-      const int g = (v0 >>  6) & 0x3fc;
-      const int b = (v0 <<  2) & 0x3fc;
-      if (!(y_pos & 1)) {  // even lines
-        u[i] = VP8RGBToU(r, g, b, YUV_HALF << 2);
-        v[i] = VP8RGBToV(r, g, b, YUV_HALF << 2);
-      } else {             // odd lines (note: we could just skip this)
-        const int tmp_u = VP8RGBToU(r, g, b, YUV_HALF << 2);
-        const int tmp_v = VP8RGBToV(r, g, b, YUV_HALF << 2);
-        u[i] = (u[i] + tmp_u + 1) >> 1;
-        v[i] = (v[i] + tmp_v + 1) >> 1;
-      }
-    }
   }
   // Lastly, store alpha if needed.
   if (buf->a != NULL) {
-    int i;
     uint8_t* const a = buf->a + y_pos * buf->a_stride;
-    for (i = 0; i < width; ++i) a[i] = (src[i] >> 24);
+#if defined(WORDS_BIGENDIAN)
+    WebPExtractAlpha((uint8_t*)src + 0, 0, width, 1, a, 0);
+#else
+    WebPExtractAlpha((uint8_t*)src + 3, 0, width, 1, a, 0);
+#endif
   }
 }
 
@@ -713,7 +676,7 @@ static void ProcessRows(VP8LDecoder* const dec, int row) {
       // Nothing to output (this time).
     } else {
       const WebPDecBuffer* const output = dec->output_;
-      if (output->colorspace < MODE_YUV) {  // convert to RGBA
+      if (WebPIsRGBMode(output->colorspace)) {  // convert to RGBA
         const WebPRGBABuffer* const buf = &output->u.RGBA;
         uint8_t* const rgba = buf->rgba + dec->last_out_row_ * buf->stride;
         const int num_rows_out = io->use_scaling ?
@@ -1552,6 +1515,10 @@ int VP8LDecodeImage(VP8LDecoder* const dec) {
       // need the alpha-multiply functions for premultiplied output or rescaling
       WebPInitAlphaProcessing();
     }
+    if (!WebPIsRGBMode(dec->output_->colorspace)) {
+      WebPInitConvertARGBToYUV();
+      if (dec->output_->u.YUVA.a != NULL) WebPInitAlphaProcessing();
+    }
     if (dec->incremental_) {
       if (dec->hdr_.color_cache_size_ > 0 &&
           dec->hdr_.saved_color_cache_.colors_ == NULL) {

src/dsp/dsp.h

@@ -324,6 +324,19 @@ void WebPInitSamplers(void);
 // Must be called before using WebPYUV444Converters[]
 void WebPInitYUV444Converters(void);
 
+//------------------------------------------------------------------------------
+// ARGB -> YUV converters (for lossless decoding)
+
+// Convert ARGB samples to luma Y.
+extern void (*WebPConvertARGBToY)(const uint32_t* argb, uint8_t* y, int width);
+// Convert ARGB samples to U/V with downsampling. do_store should be '1' for
+// even lines and '0' for odd ones. 'src_width' is the original width, not
+// the U/V one.
+extern void (*WebPConvertARGBToUV)(const uint32_t* argb, uint8_t* u, uint8_t* v,
+                                   int src_width, int do_store);
+// Must be called before using WebPConvertARGBToXXX
+void WebPInitConvertARGBToYUV(void);
+
 //------------------------------------------------------------------------------
 // Rescaler
 

src/dsp/yuv.c

@@ -164,3 +164,74 @@ WEBP_TSAN_IGNORE_FUNCTION void WebPInitSamplers(void) {
 }
 
 //-----------------------------------------------------------------------------
+// ARGB -> YUV converters (for lossless decoding)
+
+static void ConvertARGBToY(const uint32_t* argb, uint8_t* y, int width) {
+  int i;
+  for (i = 0; i < width; ++i) {
+    const uint32_t p = argb[i];
+    y[i] = VP8RGBToY((p >> 16) & 0xff, (p >> 8) & 0xff, (p >>  0) & 0xff,
+                     YUV_HALF);
+  }
+}
+static void ConvertARGBToUV(const uint32_t* argb, uint8_t* u, uint8_t* v,
+                            int src_width, int do_store) {
+  // No rounding. Last pixel is dealt with separately.
+  const int uv_width = src_width >> 1;
+  int i;
+  for (i = 0; i < uv_width; ++i) {
+    const uint32_t v0 = argb[2 * i + 0];
+    const uint32_t v1 = argb[2 * i + 1];
+    // VP8RGBToU/V expects four accumulated pixels. Hence we need to
+    // scale r/g/b value by a factor 2. We just shift v0/v1 one bit less.
+    const int r = ((v0 >> 15) & 0x1fe) + ((v1 >> 15) & 0x1fe);
+    const int g = ((v0 >>  7) & 0x1fe) + ((v1 >>  7) & 0x1fe);
+    const int b = ((v0 <<  1) & 0x1fe) + ((v1 <<  1) & 0x1fe);
+    const int tmp_u = VP8RGBToU(r, g, b, YUV_HALF << 2);
+    const int tmp_v = VP8RGBToV(r, g, b, YUV_HALF << 2);
+    if (do_store) {
+      u[i] = tmp_u;
+      v[i] = tmp_v;
+    } else {
+      // Approximated average-of-four. But it's an acceptable diff.
+      u[i] = (u[i] + tmp_u + 1) >> 1;
+      v[i] = (v[i] + tmp_v + 1) >> 1;
+    }
+  }
+  if (src_width & 1) {       // last pixel
+    const uint32_t v0 = argb[2 * i + 0];
+    const int r = (v0 >> 14) & 0x3fc;
+    const int g = (v0 >>  6) & 0x3fc;
+    const int b = (v0 <<  2) & 0x3fc;
+    const int tmp_u = VP8RGBToU(r, g, b, YUV_HALF << 2);
+    const int tmp_v = VP8RGBToV(r, g, b, YUV_HALF << 2);
+    if (do_store) {
+      u[i] = tmp_u;
+      v[i] = tmp_v;
+    } else {
+      u[i] = (u[i] + tmp_u + 1) >> 1;
+      v[i] = (v[i] + tmp_v + 1) >> 1;
+    }
+  }
+}
+
+void (*WebPConvertARGBToY)(const uint32_t* argb, uint8_t* y, int width);
+void (*WebPConvertARGBToUV)(const uint32_t* argb, uint8_t* u, uint8_t* v,
+                            int src_width, int do_store);
+static volatile VP8CPUInfo rgba_to_yuv_last_cpuinfo_used =
+    (VP8CPUInfo)&rgba_to_yuv_last_cpuinfo_used;
+
+WEBP_TSAN_IGNORE_FUNCTION void WebPInitConvertARGBToYUV(void) {
+  if (rgba_to_yuv_last_cpuinfo_used == VP8GetCPUInfo) return;
+
+  WebPConvertARGBToY = ConvertARGBToY;
+  WebPConvertARGBToUV = ConvertARGBToUV;
+
+  if (VP8GetCPUInfo != NULL) {
+#if defined(WEBP_USE_SSE2)
+    if (VP8GetCPUInfo(kSSE2)) {
+    }
+#endif  // WEBP_USE_SSE2
+  }
+  rgba_to_yuv_last_cpuinfo_used = VP8GetCPUInfo;
+}