audiovideo_V4L2: Added more pixel formats.

client/site_tests/audiovideo_V4L2/src/media_v4l2_test.cc

 // Copyright (c) 2010 The Chromium OS Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include <assert.h>
 #include <getopt.h>
 #include <signal.h>
 #include <X11/Xlib.h>
 
 #include <iostream>
@@ skipping 104 matching lines @@
     XFreeGC(xdisplay_, gc);
   }
 
   inline int32_t clip(int32_t value, int32_t min, int32_t max) {
     return (value > max ? max : value < min ? min : value);
   }
 
   void ConvertYUVToRGB32(uint8_t* in, uint8_t* out, int32_t ifmt,
                          int32_t width, int32_t height,
                          int32_t istride, int32_t ostride) {
-    if (ifmt == v4l2_fourcc('Y', 'U', 'Y', 'V')) {
+    if ((ifmt == v4l2_fourcc('Y', 'U', 'Y', 'V')) ||
+        (ifmt == v4l2_fourcc('Y', 'V', 'Y', 'U')) ||
+        (ifmt == v4l2_fourcc('U', 'Y', 'V', 'Y')) ||
+        (ifmt == v4l2_fourcc('V', 'Y', 'U', 'Y'))) {
       for (int32_t i = 0; i < height; ++i) {
         for (int32_t j = 0; j < width * 2; j += 4) {
-           int32_t y0 = in[j];
-           int32_t y1 = in[j + 2];
-           int32_t u = in[j + 1] - 128;
-           int32_t v = in[j + 3] - 128;
+          int32_t y0;
+          int32_t y1;
+          int32_t u;
+          int32_t v;
 
-           int32_t r = (298 * y0 + 409 * v + 128) >> 8;
-           int32_t g = (298 * y0 - 100 * u - 208 * v + 128) >> 8;
-           int32_t b = (298 * y0 + 516 * u + 128) >> 8;
-           out[j * 2 + 0] = clip(b, 0, 255);
-           out[j * 2 + 1] = clip(g, 0, 255);
-           out[j * 2 + 2] = clip(r, 0, 255);
-           out[j * 2 + 3] = 255;
-           r = (298 * y1 + 409 * v + 128) >> 8;
-           g = (298 * y1 - 100 * u - 208 * v + 128) >> 8;
-           b = (298 * y1 + 516 * u + 128) >> 8;
-           out[j * 2 + 4] = clip(b, 0, 255);
-           out[j * 2 + 5] = clip(g, 0, 255);
-           out[j * 2 + 6] = clip(r, 0, 255);
-           out[j * 2 + 7] = 255;
+          if (ifmt == v4l2_fourcc('Y', 'U', 'Y', 'V')) {
+            y0 = in[j];
+            y1 = in[j + 2];
+            u = in[j + 1] - 128;
+            v = in[j + 3] - 128;
+          } else if (ifmt == v4l2_fourcc('Y', 'V', 'Y', 'U')) {
+            y0 = in[j];
+            y1 = in[j + 2];
+            u = in[j + 3] - 128;
+            v = in[j + 1] - 128;
+          } else if (ifmt == v4l2_fourcc('U', 'Y', 'V', 'Y')) {
+            y0 = in[j + 1];
+            y1 = in[j + 3];
+            u = in[j] - 128;
+            v = in[j + 2] - 128;
+          } else if (ifmt == v4l2_fourcc('V', 'Y', 'U', 'Y')) {
+            y0 = in[j + 1];
+            y1 = in[j + 3];
+            u = in[j + 2] - 128;
+            v = in[j] - 128;
+          } else {
+            CHECK(0);
+          }

[jiesun, 2011/04/28 17:28:27]

I actually prefer to do the branching outside the main loop.
using y0_offset, y1_offset, and u_offset, and v_offset...
save some cpu..

+
+          int32_t r = (298 * y0 + 409 * v + 128) >> 8;
+          int32_t g = (298 * y0 - 100 * u - 208 * v + 128) >> 8;
+          int32_t b = (298 * y0 + 516 * u + 128) >> 8;
+
+          out[j * 2 + 0] = clip(b, 0, 255);
+          out[j * 2 + 1] = clip(g, 0, 255);
+          out[j * 2 + 2] = clip(r, 0, 255);
+          out[j * 2 + 3] = 255;
+
+          r = (298 * y1 + 409 * v + 128) >> 8;
+          g = (298 * y1 - 100 * u - 208 * v + 128) >> 8;
+          b = (298 * y1 + 516 * u + 128) >> 8;
+
+          out[j * 2 + 4] = clip(b, 0, 255);
+          out[j * 2 + 5] = clip(g, 0, 255);
+          out[j * 2 + 6] = clip(r, 0, 255);
+          out[j * 2 + 7] = 255;
         }
         in += istride;
         out += ostride;
       }
+    } else if (ifmt == v4l2_fourcc('Y', 'U', '1', '2')) {

[jiesun, 2011/04/28 17:32:31]

|| ifmt == v4l2_fourcc('Y', 'V', '1', '2')
since in another patch, you said YV12 is done.

+      // Can't use pixels_per_line for this.  While pixels per line is 12,
+      // the rest of this part of code is using line stride as the
+      // y-plane's line stride, which should just be the width of the image.
+      istride = width;
+
+      uint8_t* y_plane = in;
+      uint8_t* u_plane = in + height * istride;
+      // assumption. stride for uv is half of the y stride.
+      uint8_t* v_plane = u_plane + height * istride / 4;

[jiesun, 2011/04/28 17:32:31]

if (ifmt == v4l2_fourcc('Y', 'V', '1', '2')) swap the u_plane and v_plane. 

+      for (int32_t i = 0; i < height; ++i) {
+        for (int32_t j = 0; j < width; ++j) {
+          int32_t y = y_plane[j];
+          int32_t u = u_plane[j>>1];

[jiesun, 2011/04/28 17:28:27]

apparently that I had forgetten to -128 here and the line below.

+          int32_t v = v_plane[j>>1];

[jiesun, 2011/04/28 17:28:27]

please also add space around binary operator >>.

+
+          int32_t r = (298 * y + 409 * v + 128) >> 8;
+          int32_t g = (298 * y - 100 * u - 208 * v + 128) >> 8;
+          int32_t b = (298 * y + 516 * u + 128) >> 8;
+
+          out[j * 4 + 0] = clip(b, 0, 255);
+          out[j * 4 + 1] = clip(g, 0, 255);
+          out[j * 4 + 2] = clip(r, 0, 255);
+          out[j * 4 + 3] = 255;
+        }
+        y_plane += istride;
+        if (i&1) {
+          u_plane += istride >> 1;
+          v_plane += istride >> 1;
+        }
+        out += ostride;
+      }
     } else {
       CHECK(0);
     }
   }
 
  private:
   Display* xdisplay_;
   Window xwindow_;
   XImage* ximage_;
   bool xrunning_;
@@ skipping 147 matching lines @@
     retcode = 6;
 
   device->CloseDevice();
 
   if (device)
     delete device;
 
   return retcode;
 }