Pepper: add Image Capture interfaces.

ppapi/api/private/ppb_camera_capabilities_private.idl

+/* Copyright (c) 2014 The Chromium Authors. All rights reserved.

[Justin Chuang, 2014/08/11 08:32:35]

nit: copyright disclaimer no longer contains "(c)" in latest coding convention.

http://www.chromium.org/developers/coding-style#TOC-File-headers

[wuchengli, 2014/08/12 07:27:02]

Done.

+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+/**
+ * This file defines the PPB_CameraCapabilities_Private interface for
+ * establishing an image capture configuration resource within the browser.
+ */
+
+[generate_thunk]
+
+label Chrome {
+  M39 = 0.1
+};
+
+/**
+ * The <code>PPB_CameraCapabilities_Private</code> interface contains pointers
+ * to several functions for getting the image capture capabilities within the
+ * browser.
+ */
+[version=0.1]
+interface PPB_CameraCapabilities_Private {
+  /**
+   * IsCameraCapabilities() determines if the given resource is a
+   * <code>PPB_CameraCapabilities_Private</code>.
+   *
+   * @param[in] resource A <code>PP_Resource</code> corresponding to an image
+   * capture capabilities resource.
+   *
+   * @return A <code>PP_Bool</code> containing <code>PP_TRUE</code> if the given
+   * resource is an <code>PP_CameraCapabilities_Private</code> resource,
+   * otherwise <code>PP_FALSE</code>.
+   */
+  PP_Bool IsCameraCapabilities(
+      [in] PP_Resource resource);
+
+  /**
+   * GetSupportedPreviewSizes() returns the supported preview sizes for the given
+   * <code>PPB_CameraCapabilities_Private</code>.
+   *
+   * @param[in] capabilities A <code>PP_Resource</code> corresponding to an
+   * image capture capabilities resource.
+   * @param[out] array_size The size of preview size array.
+   * @param[out] An array of <code>PP_Size</code> corresponding to the supported
+   * preview sizes in pixels. The ownership of the array belongs to <code>
+   * PPB_CameraCapabilities_Private</code> and the caller should not free it.

[dmichael (off chromium), 2014/08/08 21:13:05]

Ah, I see! That sounds like a good approach in this case.

[wuchengli, 2014/08/12 07:27:02]

Acknowledged.

+   */
+  void GetSupportedPreviewSizes(
+      [in] PP_Resource capabilities,
+      [out] int32_t array_size,
+      [out, size_is(array_size)] PP_Size[] preview_sizes);

[dmichael (off chromium), 2014/08/08 21:23:07]

By the way, in case it isn't obvious...  you'll want to just allocate that array
(really probably a vector) when the internal proxy object is created, and never
delete it. You might note that when a PPB_CameraCapabilities_Private is deleted,
the arrays resulting from GetSupported*Sizes are no longer valid.

You don't want to get in to wacky thread race conditions by being too clever
about the array lifetime.

[wuchengli, 2014/08/12 07:27:02]

Done. I　ａｄｄｅｄ the comments.

+
+  /**
+   * GetSupportedJpegSize() returns the supported JPEG sizes for the given
+   * <code>PPB_CameraCapabilities_Private</code>.
+   *
+   * @param[in] capabilities A <code>PP_Resource</code> corresponding to an
+   * image capture capabilities resource.
+   * @param[out] array_size The size of JPEG size array. If the output of this
+   * is 0, the camera has no support for generating JPEG images.
+   * @param[out] An array of <code>PP_Size</code> corresponding to the supported
+   * JPEG image sizes in pixels. The ownership of the array belongs to <code>
+   * PPB_CameraCapabilities_Private</code> and the caller should not free it.
+   */
+  void GetSupportedJpegSizes(

[dmichael (off chromium), 2014/08/08 21:13:05]

I assume you expect this resource to have its data completely on the
plugin-side, so these Get functions don't have to do IPC or anything. Is that
right? Sounds like a good approach to me...

(otherwise these should have completion callbacks and be async; but I think we
can avoid that)

[wuchengli, 2014/08/12 07:27:01]

Yes. The data is completely on the plugin-side and IPC is not required.

+      [in] PP_Resource capabilities,
+      [out] int32_t array_size,
+      [out, size_is(array_size)] PP_Size[] jpeg_sizes);
+};