Camera: document expected thumbnail size in capture result

Bug: 21880406
Change-Id: I05a3f9731715a5906a13ba5f8647c887df73b6a7
diff --git a/camera/docs/docs.html b/camera/docs/docs.html
index e3e1c07..f8cecb2 100644
--- a/camera/docs/docs.html
+++ b/camera/docs/docs.html
@@ -10386,6 +10386,18 @@
 16:9 aspect ratio,<wbr/> the primary image will be cropped vertically (letterbox) to
 generate the thumbnail image.<wbr/> The thumbnail image will always have a smaller Field
 Of View (FOV) than the primary image when aspect ratios differ.<wbr/></p>
+<p>When an <a href="#controls_android.jpeg.orientation">android.<wbr/>jpeg.<wbr/>orientation</a> of non-zero degree is requested,<wbr/>
+the camera device will handle thumbnail rotation in one of the following ways:</p>
+<ul>
+<li>Set the <a href="https://developer.android.com/reference/android/media/ExifInterface.html#TAG_ORIENTATION">EXIF orientation flag</a>
+  and keep jpeg and thumbnail image data unrotated.<wbr/></li>
+<li>Rotate the jpeg and thumbnail image data and not set
+  <a href="https://developer.android.com/reference/android/media/ExifInterface.html#TAG_ORIENTATION">EXIF orientation flag</a>.<wbr/> In this
+  case,<wbr/> LIMITED or FULL hardware level devices will report rotated thumnail size in
+  capture result,<wbr/> so the width and height will be interchanged if 90 or 270 degree
+  orientation is requested.<wbr/> LEGACY device will always report unrotated thumbnail
+  size.<wbr/></li>
+</ul>
             </td>
           </tr>
 
@@ -11043,6 +11055,18 @@
 16:9 aspect ratio,<wbr/> the primary image will be cropped vertically (letterbox) to
 generate the thumbnail image.<wbr/> The thumbnail image will always have a smaller Field
 Of View (FOV) than the primary image when aspect ratios differ.<wbr/></p>
+<p>When an <a href="#controls_android.jpeg.orientation">android.<wbr/>jpeg.<wbr/>orientation</a> of non-zero degree is requested,<wbr/>
+the camera device will handle thumbnail rotation in one of the following ways:</p>
+<ul>
+<li>Set the <a href="https://developer.android.com/reference/android/media/ExifInterface.html#TAG_ORIENTATION">EXIF orientation flag</a>
+  and keep jpeg and thumbnail image data unrotated.<wbr/></li>
+<li>Rotate the jpeg and thumbnail image data and not set
+  <a href="https://developer.android.com/reference/android/media/ExifInterface.html#TAG_ORIENTATION">EXIF orientation flag</a>.<wbr/> In this
+  case,<wbr/> LIMITED or FULL hardware level devices will report rotated thumnail size in
+  capture result,<wbr/> so the width and height will be interchanged if 90 or 270 degree
+  orientation is requested.<wbr/> LEGACY device will always report unrotated thumbnail
+  size.<wbr/></li>
+</ul>
             </td>
           </tr>
 
diff --git a/camera/docs/metadata_properties.xml b/camera/docs/metadata_properties.xml
index 2bac770..bd880e8 100644
--- a/camera/docs/metadata_properties.xml
+++ b/camera/docs/metadata_properties.xml
@@ -3061,6 +3061,18 @@
           16:9 aspect ratio, the primary image will be cropped vertically (letterbox) to
           generate the thumbnail image. The thumbnail image will always have a smaller Field
           Of View (FOV) than the primary image when aspect ratios differ.
+
+          When an android.jpeg.orientation of non-zero degree is requested,
+          the camera device will handle thumbnail rotation in one of the following ways:
+
+          * Set the {@link android.media.ExifInterface#TAG_ORIENTATION EXIF orientation flag}
+            and keep jpeg and thumbnail image data unrotated.
+          * Rotate the jpeg and thumbnail image data and not set
+            {@link android.media.ExifInterface#TAG_ORIENTATION EXIF orientation flag}. In this
+            case, LIMITED or FULL hardware level devices will report rotated thumnail size in
+            capture result, so the width and height will be interchanged if 90 or 270 degree
+            orientation is requested. LEGACY device will always report unrotated thumbnail
+            size.
           </details>
           <hal_details>
           The HAL must not squeeze or stretch the downscaled primary image to generate thumbnail.