Fix thumbnail rotation in getBitmap() - #331
Open
Seyun wants to merge 1 commit into
Open
Conversation
MediaMetadataRetriever.getFrameAtTime() returns the frame bitmap in its raw encoded orientation without applying the video's rotation metadata. For a portrait-recorded video (raw encoded landscape + 90/270 rotation flag), this produced a landscape-looking thumbnail even though the video itself plays back correctly rotated. Read METADATA_KEY_VIDEO_ROTATION alongside the frame and rotate the extracted bitmap to match before returning it.
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
1 participant
Add this suggestion to a batch that can be applied as a single commit.This suggestion is invalid because no changes were made to the code.Suggestions cannot be applied while the pull request is closed.Suggestions cannot be applied while viewing a subset of changes.Only one suggestion per line can be applied in a batch.Add this suggestion to a batch that can be applied as a single commit.Applying suggestions on deleted lines is not supported.You must change the existing code in this line in order to create a valid suggestion.Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be applied on multi-line comments.Suggestions cannot be applied while the pull request is queued to merge.Suggestion cannot be applied right now. Please check back later.
What
getBitmap()(Android) extracts the poster frame viaMediaMetadataRetriever.getFrameAtTime(), but never applied the video's rotation metadata to the resulting bitmap.Why it matters
getFrameAtTime()returns the frame in its raw encoded orientation, ignoring the rotation flag — this is standard, well-documented Android behavior. Portrait recordings are frequently encoded with landscape raw dimensions plus a 90°/270° rotation flag, so the extracted thumbnail bitmap came out sideways even though the video itself plays back correctly rotated (players honor the rotation metadata; frame-grabbing viagetFrameAtTime()does not).Fix
Read
METADATA_KEY_VIDEO_ROTATIONalongside the frame and rotate the extracted bitmap with aMatrixto match the actual playback orientation before it's scaled/returned.