| // Copyright 2019 The Chromium 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 "content/renderer/accessibility/ax_image_annotator.h" |
| |
| #include <ctype.h> |
| #include <utility> |
| #include <vector> |
| |
| #include "base/base64.h" |
| #include "base/stl_util.h" |
| #include "base/strings/string_number_conversions.h" |
| #include "base/strings/utf_string_conversions.h" |
| #include "content/app/strings/grit/content_strings.h" |
| #include "content/public/common/content_client.h" |
| #include "content/renderer/render_frame_impl.h" |
| #include "crypto/sha2.h" |
| #include "third_party/blink/public/web/web_ax_object.h" |
| #include "third_party/blink/public/web/web_document.h" |
| #include "third_party/blink/public/web/web_element.h" |
| #include "third_party/blink/public/web/web_local_frame.h" |
| #include "third_party/blink/public/web/web_node.h" |
| #include "ui/gfx/geometry/size.h" |
| #include "url/gurl.h" |
| |
| namespace content { |
| |
| AXImageAnnotator::AXImageAnnotator( |
| RenderAccessibilityImpl* const render_accessibility, |
| const std::string& preferred_language, |
| image_annotation::mojom::AnnotatorPtr annotator_ptr) |
| : render_accessibility_(render_accessibility), |
| preferred_language_(preferred_language), |
| annotator_ptr_(std::move(annotator_ptr)), |
| weak_factory_(this) { |
| DCHECK(render_accessibility_); |
| } |
| |
| AXImageAnnotator::~AXImageAnnotator() {} |
| |
| void AXImageAnnotator::Destroy() { |
| MarkAllImagesDirty(); |
| } |
| |
| std::string AXImageAnnotator::GetImageAnnotation( |
| blink::WebAXObject& image) const { |
| DCHECK(!image.IsDetached()); |
| const auto lookup = image_annotations_.find(image.AxID()); |
| if (lookup != image_annotations_.end()) |
| return lookup->second.annotation(); |
| return std::string(); |
| } |
| |
| ax::mojom::ImageAnnotationStatus AXImageAnnotator::GetImageAnnotationStatus( |
| blink::WebAXObject& image) const { |
| DCHECK(!image.IsDetached()); |
| const auto lookup = image_annotations_.find(image.AxID()); |
| if (lookup != image_annotations_.end()) |
| return lookup->second.status(); |
| return ax::mojom::ImageAnnotationStatus::kNone; |
| } |
| |
| bool AXImageAnnotator::HasAnnotationInCache(blink::WebAXObject& image) const { |
| DCHECK(!image.IsDetached()); |
| if (!HasImageInCache(image)) |
| return false; |
| return image_annotations_.at(image.AxID()).HasAnnotation(); |
| } |
| |
| bool AXImageAnnotator::HasImageInCache(const blink::WebAXObject& image) const { |
| DCHECK(!image.IsDetached()); |
| return base::ContainsKey(image_annotations_, image.AxID()); |
| } |
| |
| void AXImageAnnotator::OnImageAdded(blink::WebAXObject& image) { |
| DCHECK(!image.IsDetached()); |
| DCHECK(!base::ContainsKey(image_annotations_, image.AxID())); |
| const std::string image_id = GenerateImageSourceId(image); |
| if (image_id.empty()) |
| return; |
| |
| image_annotations_.emplace(image.AxID(), image); |
| ImageInfo& image_info = image_annotations_.at(image.AxID()); |
| // Fetch image annotation. |
| annotator_ptr_->AnnotateImage( |
| image_id, preferred_language_, image_info.GetImageProcessor(), |
| base::BindOnce(&AXImageAnnotator::OnImageAnnotated, |
| weak_factory_.GetWeakPtr(), image)); |
| VLOG(1) << "Requesting annotation for " << image_id << " with language '" |
| << preferred_language_ << "' from page " << GetDocumentUrl(); |
| } |
| |
| void AXImageAnnotator::OnImageUpdated(blink::WebAXObject& image) { |
| DCHECK(!image.IsDetached()); |
| DCHECK(base::ContainsKey(image_annotations_, image.AxID())); |
| const std::string image_id = GenerateImageSourceId(image); |
| if (image_id.empty()) |
| return; |
| |
| ImageInfo& image_info = image_annotations_.at(image.AxID()); |
| // Update annotation. |
| annotator_ptr_->AnnotateImage( |
| image_id, preferred_language_, image_info.GetImageProcessor(), |
| base::BindOnce(&AXImageAnnotator::OnImageAnnotated, |
| weak_factory_.GetWeakPtr(), image)); |
| } |
| |
| void AXImageAnnotator::OnImageRemoved(blink::WebAXObject& image) { |
| DCHECK(!image.IsDetached()); |
| auto lookup = image_annotations_.find(image.AxID()); |
| if (lookup == image_annotations_.end()) { |
| NOTREACHED() << "Removing an image that has not been added."; |
| return; |
| } |
| image_annotations_.erase(lookup); |
| } |
| |
| #if defined(CONTENT_IMPLEMENTATION) |
| ContentClient* AXImageAnnotator::GetContentClient() const { |
| return content::GetContentClient(); |
| } |
| #else |
| ContentClient* AXImageAnnotator::GetContentClient() const { |
| return nullptr; |
| } |
| #endif // defined(CONTENT_IMPLEMENTATION) |
| |
| std::string AXImageAnnotator::GenerateImageSourceId( |
| const blink::WebAXObject& image) const { |
| DCHECK(render_accessibility_); |
| DCHECK(!image.IsDetached()); |
| const std::string document_url = |
| render_accessibility_->GetMainDocument().Url().GetString().Utf8(); |
| const std::string image_src = image.Url().GetString().Utf8(); |
| if (document_url.empty() || image_src.empty()) |
| return std::string(); |
| |
| // The |image_src| might be a URL that is relative to the document's URL. |
| const GURL image_url = GURL(document_url).Resolve(image_src); |
| if (!image_url.is_valid()) |
| return std::string(); |
| |
| // If |image_url| appears to be publicly reachable, return the URL as the |
| // image source ID. |
| if (image_url.SchemeIsHTTPOrHTTPS()) |
| return image_url.spec(); |
| |
| // If |image_url| is not publicly reachable, return a hash of |image_url|. |
| // Scheme could be "data", "javascript", "ftp", "file", etc. |
| const std::string& content = image_url.GetContent(); |
| if (content.empty()) |
| return std::string(); |
| std::string source_id; |
| base::Base64Encode(crypto::SHA256HashString(content), &source_id); |
| return source_id; |
| } |
| |
| void AXImageAnnotator::MarkAllImagesDirty() { |
| for (auto& key_value : image_annotations_) { |
| blink::WebAXObject image = blink::WebAXObject::FromWebDocumentByID( |
| render_accessibility_->GetMainDocument(), key_value.first); |
| if (!image.IsDetached()) |
| MarkDirty(image); |
| } |
| image_annotations_.clear(); |
| } |
| |
| void AXImageAnnotator::MarkDirty(const blink::WebAXObject& image) const { |
| render_accessibility_->MarkWebAXObjectDirty(image, false /* subtree */); |
| |
| // Check two unignored parents. If either of them is a link or root web area, |
| // mark it dirty too, because we want a link or document containing exactly |
| // a single image and nothing more to get annotated directly, too. |
| // |
| // TODO(dmazzoni): Expose ParentObjectUnignored in WebAXObject to |
| // make this simpler. |
| blink::WebAXObject parent = image.ParentObject(); |
| for (int ancestor_count = 0; !parent.IsDetached() && ancestor_count < 2; |
| parent = parent.ParentObject()) { |
| if (!parent.AccessibilityIsIgnored()) { |
| ++ancestor_count; |
| if (parent.Role() == ax::mojom::Role::kLink || |
| parent.Role() == ax::mojom::Role::kRootWebArea) { |
| render_accessibility_->MarkWebAXObjectDirty(parent, |
| false /* subtree */); |
| return; |
| } |
| } |
| } |
| } |
| |
| AXImageAnnotator::ImageInfo::ImageInfo(const blink::WebAXObject& image) |
| : image_processor_( |
| base::BindRepeating(&AXImageAnnotator::GetImageData, image)), |
| status_(ax::mojom::ImageAnnotationStatus::kAnnotationPending), |
| annotation_(base::nullopt) {} |
| |
| AXImageAnnotator::ImageInfo::~ImageInfo() = default; |
| |
| image_annotation::mojom::ImageProcessorPtr |
| AXImageAnnotator::ImageInfo::GetImageProcessor() { |
| return image_processor_.GetPtr(); |
| } |
| |
| bool AXImageAnnotator::ImageInfo::HasAnnotation() const { |
| switch (status_) { |
| case ax::mojom::ImageAnnotationStatus::kNone: |
| case ax::mojom::ImageAnnotationStatus::kWillNotAnnotateDueToScheme: |
| case ax::mojom::ImageAnnotationStatus::kIneligibleForAnnotation: |
| // The user hasn't requested an annotation yet, or a previously pending |
| // annotation request had been cancelled. |
| case ax::mojom::ImageAnnotationStatus::kEligibleForAnnotation: |
| case ax::mojom::ImageAnnotationStatus::kAnnotationPending: |
| return false; |
| case ax::mojom::ImageAnnotationStatus::kAnnotationSucceeded: |
| DCHECK(annotation_.has_value()); |
| return true; |
| case ax::mojom::ImageAnnotationStatus::kAnnotationEmpty: |
| // Image has been classified as adult content. |
| case ax::mojom::ImageAnnotationStatus::kAnnotationAdult: |
| case ax::mojom::ImageAnnotationStatus::kAnnotationProcessFailed: |
| DCHECK(!annotation_.has_value()); |
| return true; |
| } |
| } |
| |
| // static |
| SkBitmap AXImageAnnotator::GetImageData(const blink::WebAXObject& image) { |
| if (image.IsDetached()) |
| return SkBitmap(); |
| blink::WebNode node = image.GetNode(); |
| if (node.IsNull() || !node.IsElementNode()) |
| return SkBitmap(); |
| blink::WebElement element = node.To<blink::WebElement>(); |
| VLOG(1) << "Uploading pixels for " << element.ImageContents().width() << " x " |
| << element.ImageContents().height() << " image"; |
| return element.ImageContents(); |
| } |
| |
| void AXImageAnnotator::OnImageAnnotated( |
| const blink::WebAXObject& image, |
| image_annotation::mojom::AnnotateImageResultPtr result) { |
| if (!base::ContainsKey(image_annotations_, image.AxID())) |
| return; |
| |
| if (image.IsDetached()) { |
| image_annotations_.at(image.AxID()) |
| .set_status(ax::mojom::ImageAnnotationStatus::kIneligibleForAnnotation); |
| // We should not mark dirty a detached object. |
| return; |
| } |
| |
| if (result->is_error_code()) { |
| DLOG(WARNING) << "Image annotation error."; |
| switch (result->get_error_code()) { |
| case image_annotation::mojom::AnnotateImageError::kCanceled: |
| image_annotations_.at(image.AxID()) |
| .set_status( |
| ax::mojom::ImageAnnotationStatus::kEligibleForAnnotation); |
| break; |
| case image_annotation::mojom::AnnotateImageError::kFailure: |
| image_annotations_.at(image.AxID()) |
| .set_status( |
| ax::mojom::ImageAnnotationStatus::kAnnotationProcessFailed); |
| break; |
| case image_annotation::mojom::AnnotateImageError::kAdult: |
| image_annotations_.at(image.AxID()) |
| .set_status(ax::mojom::ImageAnnotationStatus::kAnnotationAdult); |
| break; |
| } |
| MarkDirty(image); |
| return; |
| } |
| |
| if (!result->is_annotations()) { |
| DLOG(WARNING) << "No image annotation results."; |
| image_annotations_.at(image.AxID()) |
| .set_status(ax::mojom::ImageAnnotationStatus::kAnnotationEmpty); |
| MarkDirty(image); |
| return; |
| } |
| |
| std::vector<std::string> contextualized_strings; |
| for (const mojo::InlinedStructPtr<image_annotation::mojom::Annotation>& |
| annotation : result->get_annotations()) { |
| int message_id = 0; |
| switch (annotation->type) { |
| case image_annotation::mojom::AnnotationType::kOcr: |
| message_id = IDS_AX_IMAGE_ANNOTATION_OCR_CONTEXT; |
| break; |
| case image_annotation::mojom::AnnotationType::kCaption: |
| case image_annotation::mojom::AnnotationType::kLabel: |
| message_id = IDS_AX_IMAGE_ANNOTATION_DESCRIPTION_CONTEXT; |
| break; |
| } |
| |
| // Skip unrecognized annotation types. |
| if (message_id == 0) |
| continue; |
| |
| int last_meaningful_char = annotation->text.length() - 1; |
| while (last_meaningful_char >= 0) { |
| bool is_whitespace_or_punct = |
| isspace(annotation->text[last_meaningful_char]) || |
| ispunct(annotation->text[last_meaningful_char]); |
| if (!is_whitespace_or_punct) |
| break; |
| last_meaningful_char--; |
| } |
| |
| if (annotation->text.empty() || last_meaningful_char < 0) |
| continue; |
| |
| std::string text = annotation->text.substr(0, last_meaningful_char + 1); |
| if (GetContentClient()) { |
| contextualized_strings.push_back( |
| base::UTF16ToUTF8(GetContentClient()->GetLocalizedString( |
| message_id, base::UTF8ToUTF16(text)))); |
| } else { |
| contextualized_strings.push_back(text); |
| } |
| } |
| |
| if (contextualized_strings.empty()) { |
| image_annotations_.at(image.AxID()) |
| .set_status(ax::mojom::ImageAnnotationStatus::kAnnotationEmpty); |
| MarkDirty(image); |
| return; |
| } |
| |
| image_annotations_.at(image.AxID()) |
| .set_status(ax::mojom::ImageAnnotationStatus::kAnnotationSucceeded); |
| // TODO(accessibility): join two sentences together in a more i18n-friendly |
| // way. Since this is intended for a screen reader, though, a period |
| // probably works in almost all languages. |
| std::string contextualized_string = |
| base::JoinString(contextualized_strings, ". "); |
| image_annotations_.at(image.AxID()).set_annotation(contextualized_string); |
| MarkDirty(image); |
| |
| VLOG(1) << "Annotating image on page " << GetDocumentUrl() << " - " |
| << contextualized_string; |
| } |
| |
| std::string AXImageAnnotator::GetDocumentUrl() const { |
| const blink::WebLocalFrame* frame = |
| render_accessibility_->render_frame()->GetWebFrame(); |
| return frame->GetDocument().Url().GetString().Utf8(); |
| } |
| |
| } // namespace content |