Transformations are used to rotate and mirror the source surface of a blit operation. The destination rectangle is not affected by any transformation settings. 
NvMediaTransform identifies the transformations that can be applied as a combination of rotation and mirroring
Specifically, given a hypothetical 2x2 image, applying these operations would yield the following results 
 INPUT                      OUTPUT
 
+---+---+                  +---+---+
| 0 | 1 |     IDENTITY     | 0 | 1 |
+---+---+ ---------------> +---+---+
| 2 | 3 |                  | 2 | 3 |
+---+---+                  +---+---+
 
+---+---+                  +---+---+
| 0 | 1 |    ROTATE_90     | 1 | 3 |
+---+---+ ---------------> +---+---+
| 2 | 3 |                  | 0 | 2 |
+---+---+                  +---+---+
 
+---+---+                  +---+---+
| 0 | 1 |    ROTATE_180    | 3 | 2 |
+---+---+ ---------------> +---+---+
| 2 | 3 |                  | 1 | 0 |
+---+---+                  +---+---+
 
+---+---+                  +---+---+
| 0 | 1 |    ROTATE_270    | 2 | 0 |
+---+---+ ---------------> +---+---+
| 2 | 3 |                  | 3 | 1 |
+---+---+                  +---+---+
 
+---+---+                  +---+---+
| 0 | 1 |  FLIP_HORIZONTAL | 1 | 0 |
+---+---+ ---------------> +---+---+
| 2 | 3 |                  | 3 | 2 |
+---+---+                  +---+---+
 
+---+---+                  +---+---+
| 0 | 1 |  INVTRANSPOSE    | 3 | 1 |
+---+---+ ---------------> +---+---+
| 2 | 3 |                  | 2 | 0 |
+---+---+                  +---+---+
 
+---+---+                  +---+---+
| 0 | 1 |  FLIP_VERTICAL   | 2 | 3 |
+---+---+ ---------------> +---+---+
| 2 | 3 |                  | 0 | 1 |
+---+---+                  +---+---+
 
+---+---+                  +---+---+
| 0 | 1 |    TRANSPOSE     | 0 | 2 |
+---+---+ ---------------> +---+---+
| 2 | 3 |                  | 1 | 3 |
+---+---+                  +---+---+
◆ NvMediaTransform
Defines transformations. 
| Enumerator | 
|---|
| NVMEDIA_TRANSFORM_NONE | Specifies no transformation.  | 
| NVMEDIA_TRANSFORM_ROTATE_90 | Specifies rotation by 90 degrees.  | 
| NVMEDIA_TRANSFORM_ROTATE_180 | Specifies rotation by 180 degrees.  | 
| NVMEDIA_TRANSFORM_ROTATE_270 | Specifies rotation by 270 degrees.  | 
| NVMEDIA_TRANSFORM_FLIP_HORIZONTAL | Specifies horizontal mirroring.  | 
| NVMEDIA_TRANSFORM_INV_TRANSPOSE | Specifies mirroring along a diagonal axis from top right to bottom left of the rectangular region.  | 
| NVMEDIA_TRANSFORM_FLIP_VERTICAL | Specifies vertical mirroring.  | 
| NVMEDIA_TRANSFORM_TRANSPOSE | Specifies mirroring along a diagonal axis from top left to bottom right of the rectangular region.  | 
Definition at line 127 of file nvmedia_2d.h.