A ConvertFromI420 function. Supports basic conversion with no clipping, inversion or rotation, for a subset of formats - most of the single plane formats, all 3 plane formats and no 2 plane formats. (ie nv12)

BUG=none
TEST=none
Review URL: http://webrtc-codereview.appspot.com/329011

git-svn-id: http://libyuv.googlecode.com/svn/trunk@117 16f28f9a-4ce2-e073-06de-1de4eb20be90

README.chromium

@@ -1,6 +1,6 @@
 Name: libyuv
 URL: http://code.google.com/p/libyuv/
-Version: 116
+Version: 117
 License: BSD
 License File: LICENSE
 

include/libyuv/convert.h

@@ -133,6 +133,14 @@ int ConvertToI420(const uint8* src_frame, size_t src_size,
                   RotationMode rotation,
                   uint32 format);
 
+// Convert I420 to specified format.
+int ConvertFromI420(const uint8* y, int y_stride,
+                    const uint8* u, int u_stride,
+                    const uint8* v, int v_stride,
+                    uint8* dst_sample, size_t dst_sample_size,
+                    int width, int height,
+                    uint32 format);
+
 #ifdef __cplusplus
 }  // extern "C"
 }  // namespace libyuv

libyuv.gyp

@@ -37,6 +37,7 @@
         # sources
         'source/compare.cc',
         'source/convert.cc',
+        'source/convertfrom.cc',
         'source/cpu_id.cc',
         'source/format_conversion.cc',
         'source/planar_functions.cc',

source/convertfrom.cc

@@ -0,0 +1,187 @@
+/*
+ *  Copyright (c) 2011 The LibYuv project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+#include "libyuv/convert.h"
+
+#include "libyuv/basic_types.h"
+#include "libyuv/format_conversion.h"
+#include "libyuv/planar_functions.h"
+#include "video_common.h"
+
+#ifdef __cplusplus
+namespace libyuv {
+extern "C" {
+#endif
+
+// Convert I420 to specified format.
+// TODO(fbarchard): sample_size should be used to ensure the low levels do
+// not read outside the buffer provided.  It is measured in bytes and is the
+// size of the frame.  With MJPEG it is the compressed size of the frame.
+// TODO(fbarchard): add I400, I444 and RAW support.
+int ConvertFromI420(const uint8* y, int y_stride,
+                    const uint8* u, int u_stride,
+                    const uint8* v, int v_stride,
+                    uint8* dst_sample, size_t dst_sample_size,
+                    int width, int height,
+                    uint32 format) {
+  if (y == NULL || u == NULL || v == NULL || dst_sample == NULL) {
+    return -1;
+  }
+  switch (format) {
+    // Single plane formats
+    case FOURCC_YUY2:
+      I420ToYUY2(y, y_stride,
+                 u, u_stride,
+                 v, v_stride,
+                 dst_sample, width * 2,
+                 width, height);
+      break;
+    case FOURCC_UYVY:
+      I420ToUYVY(y, y_stride,
+                 u, u_stride,
+                 v, v_stride,
+                 dst_sample, width * 2,
+                 width, height);
+      break;
+    case FOURCC_24BG:
+      I420ToRGB24(y, y_stride,
+                  u, u_stride,
+                  v, v_stride,
+                  dst_sample, width * 3,
+                  width, height);
+      break;
+#ifdef HAVEI420TOBAYER
+    case FOURCC_RAW:
+      I420ToRAW(y, y_stride,
+                u, u_stride,
+                v, v_stride,
+                dst_sample, width * 3,
+                width, height);
+      break;
+#endif
+    case FOURCC_ARGB:
+      I420ToARGB(y, y_stride,
+                 u, u_stride,
+                 v, v_stride,
+                 dst_sample, width * 4,
+                 width, height);
+      break;
+    case FOURCC_BGRA:
+      I420ToBGRA(y, y_stride,
+                 u, u_stride,
+                 v, v_stride,
+                 dst_sample, width * 4,
+                 width, height);
+      break;
+    case FOURCC_ABGR:
+      I420ToABGR(y, y_stride,
+                 u, u_stride,
+                 v, v_stride,
+                 dst_sample, width * 4,
+                 width, height);
+      break;
+#ifdef HAVEI420TOBAYER
+    case FOURCC_BGGR:
+    case FOURCC_RGGB:
+    case FOURCC_GRBG:
+    case FOURCC_GBRG:
+      I420ToBayerRGB(y, y_stride,
+                     u, u_stride,
+                     v, v_stride,
+                     dst_sample, width, format,
+                     width, height);
+      break;
+#endif
+#ifdef HAVEI420TOI400
+    case FOURCC_I400:
+      I420ToI400(y, y_stride,
+                 u, u_stride,
+                 v, v_stride,
+                 dst_sample, width,
+                 width, height);
+      break;
+#endif
+    // Triplanar formats
+    case FOURCC_I420:
+    case FOURCC_YV12: {
+      int halfwidth = (width + 1) / 2;
+      int halfheight = (height + 1) / 2;
+      uint8* dst_u;
+      uint8* dst_v;
+      if (format == FOURCC_I420) {
+        dst_u = dst_sample + width * height;
+        dst_v = dst_u + halfwidth * halfheight;
+      } else {
+        dst_v = dst_sample + width * height;
+        dst_u = dst_v + halfwidth * halfheight;
+      }
+      I420Copy(y, y_stride,
+               u, u_stride,
+               v, v_stride,
+               dst_sample, width,
+               dst_u, halfwidth,
+               dst_v, halfwidth,
+               width, height);
+      break;
+    }
+    case FOURCC_I422:
+    case FOURCC_YV16: {
+      int halfwidth = (width + 1) / 2;
+      uint8* dst_u;
+      uint8* dst_v;
+      if (format == FOURCC_I422) {
+        dst_u = dst_sample + width * height;
+        dst_v = dst_u + halfwidth * height;
+      } else {
+        dst_v = dst_sample + width * height;
+        dst_u = dst_v + halfwidth * height;
+      }
+      I420ToI422(y, y_stride,
+                 u, u_stride,
+                 v, v_stride,
+                 dst_sample, width,
+                 dst_u, halfwidth,
+                 dst_v, halfwidth,
+                 width, height);
+      break;
+    }
+#ifdef HAVEI420TOI444
+    case FOURCC_I444:
+    case FOURCC_YV24: {
+      uint8* dst_u;
+      uint8* dst_v;
+      if (format == FOURCC_I444) {
+        dst_u = dst_sample + width * height;
+        dst_v = dst_u + width * height;
+      } else {
+        dst_v = dst_sample + width * height;
+        dst_u = dst_v + width * height;
+      }
+      I420ToI444(y, y_stride,
+                 u, u_stride,
+                 v, v_stride,
+                 dst_sample, width,
+                 dst_u, width,
+                 dst_v, width,
+                 width, height);
+      break;
+    }
+#endif
+    // Formats not supported - MJPG, biplanar, some rgb formats.
+    default:
+      return -1;  // unknown fourcc - return failure code.
+  }
+  return 0;
+}
+
+#ifdef __cplusplus
+}  // extern "C"
+}  // namespace libyuv
+#endif