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SC1-2-2-video-element-without-track

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Status

Version 0: Draft

Description

This test checks captions in video elements without a track element.

There are three different situations when a track element is not required

  • Video is a media alternative for text and labelled as such
  • Audio describing video-only content
  • Video contains open captions

This procedure describes those situations

Background

Assumptions

  • Test device renders html5 video (phantomJS doesn't render)

Test properties

Property Possible values
Success Criterion
  • 1.2.2
Test mode
  • SemiAuto
Test environment
  • DOM and CSS + media API to render frames as images
Test subject
  • DOM document fragment
User expertise and skills

For manual tests only:

  • no prior knowledge
User profile For manual tests only:
any additional requirements, such as language skills, use of AT etc.

Test procedure

Selector

Property Possible values
Mode
  • automatic

<VIDEO> not containing a TRACK attribute

Step 1

Property Possible values
Mode
  • Manual
  • Check if the main content contains text (hl: this could be an extra, automatic, step)
  • IF the main content doesn't have text.
    • GO TO step 2
  • IF the Video is labelled a media alternative for the text.
    • IF the Video contains more information than the text
      • RETURN SC122media-not-alternative-for-text
    • ELSE
      • RETURN SC122media-alternative-for-text

There is currently no technology to make the label programmatically determinable. hl: is this - in theory - not possible using aria-labelledby or zria-describedby?

Property Value
TestCase SC122media-alternative-for-text
Identifier {{{id}}}
Outcome passed
Pointer position
Info


Property Value
TestCase SC122media-not-alternative-for-text
Identifier {{{id}}}
Outcome failed
ErrorMessage {{{error}}}
Pointer position
Info F75: media presents more information than is presented on the page


Step 2

Property Possible values
Mode
  • manual
  • Listen to the audio
  • IF the audio is describing video-only content
    • RETURN SC122-video-only-added-audio

QUESTION: how can we automatic determine video-only content if audio is added?

Property Value
TestCase SC122-video-only-added-audio
Identifier {{{id}}}
Outcome passed
Pointer position
Info


Step 3

Property Possible values
Mode
  • automatic

First check if the video doesn't contain text at all.

  • Check if any of the video frames (may use samples nth seconds) includes text
  • IF none
    • RETURN SC122-video-no-open-captions
Property Value
TestCase SC122-video-no-open-captions
Identifier {{{id}}}
Outcome failed
ErrorMessage no caption provided with the video
Pointer position
Info


Step 4

Property Possible values
Mode
  • semi-automatic
  • FOR EACH spoken audio fragment
    • FOR EACH of the corresponding video frames
      • IF the corresponding video frame contains text
        • NEXT audio fragment
    • (NO text found in all frames for this audio fragment)
      • RETURN SC122video-all-dialogs

Probably more forgiving: 80% of spoken audio fragments should include text?

Property Value
TestCase SC122video-all-dialogs
Identifier {{{id}}}
Outcome failed
ErrorMessage Not all dialogs are covered in the captions
Pointer position
Info


Step 5

Property Possible values
Mode
  • manual
  • FOR EACH spoken audio fragment
    • IF the content of the spoken text has NOT the same meaning as the caption text
      • RETURN SC122-video-caption-meaning
Property Value
TestCase SC122-video-caption-meaning
Identifier {{{id}}}
Outcome failed
ErrorMessage The text of the captions doesn't correspond to the spoken text
Pointer position
Info


Step 6

From this step we will check if non spoken visual information captured, captions are more than subtitles.

Property Possible values
Mode
  • semi-automatic

Check to see is a speaker is presented in a fixed frame with unchanging background ('talking head' video).

  • FOR EACH frame (between intro frame and end screen)
    • IF the frame contains a head similar to the previous frame.
      • RETURN SC122-video-captions-provided
Property Value
TestCase SC122-video-captions-provided
Identifier {{{id}}}
Outcome passed
Pointer position
Info


NOTE: not sure if we should add this step, but if this step can be done fully automatic with frame scanning, we can skip additional manual steps.

Step 7

Property Possible values
Mode
  • manual

Check for each sound if it is important and has descriptive text

Property Value
TestCase SC 1.2.2 video
Identifier {{{id}}}
Outcome failed
ErrorMessage Important sound not explained in the caption
Pointer video-id and timecode
Info


Step 8

Property Possible values
Mode
  • manual

Check for each background fragment if it is important and the corresponding frame has a captioned text

Property Value
TestCase SC 1.2.2 video
Identifier {{{id}}}
Outcome failed
ErrorMessage Location not explained in the caption
Pointer videoid and timecode
Info


Step 9

Property Possible values
Mode
  • manual

Check for each speaker fragment if its frame has a captioned identification

Property Value
TestCase SC 1.2.2 video
Identifier {{{id}}}
Outcome failed
ErrorMessage Speaker not identified in the captions
Pointer position
Info


Step 10

Property Possible values
Mode
  • manual

Check for each emotion if it is important and the corresponding frame has a descriptive text

Property Value
TestCase SC 1.2.2 video
Identifier {{{id}}}
Outcome failed
ErrorMessage Emotion not explained in the caption
Pointer position
Info


Property Value
TestCase SC 1.2.2 video
Identifier {{{id}}}
Outcome passed
Pointer position
Info


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