iOS Swift中PHPhotoLibrary保存带文字视频报Cocoa错误-1的原因

Hey there, let's break down why you're hitting that frustrating Cocoa error -1 when saving your text-overlaid image video to the Photos app. This error in the context of PHPhotoLibrary typically points to a general invalid operation, and it's almost always linked to issues with your processed media or how you're preparing it for saving. Here are the most likely culprits:

1. Corrupted or Incompatible Image Data After Text Rendering #

Your textToImage method might be producing a UIImage that's either damaged or doesn't meet Photos Library's format requirements:

• Color Space Mismatch: If you're rendering text into an image using a CMYK color space instead of RGB (the standard for Photos), the library will reject it.
• Missing CGImage Backing: The generated imageWithText might not have a valid underlying CGImage (check if imageWithText.cgImage is nil).
• Invalid Image Dimensions: Extremely large or non-standard image sizes can cause processing failures.

Quick validation check you can run right after generating imageWithText:

guard let imageData = imageWithText.jpegData(compressionQuality: 0.8) else {
    print("Error: Generated image has invalid data")
    return
}
// If this passes, your image data is at least structurally sound

2. Misconfigured Video Composition/Export #

When converting your modified image to a video, small mistakes in the video setup can trigger this error:

• Unsupported Export Preset: Using a non-standard export preset (instead of something like AVAssetExportPresetHighestQuality) can produce a video the Photos Library can't parse.
• Invalid Container Format: Saving the video with an unsupported file extension (not .mov or .mp4) will cause rejection.
• Broken Asset Tracks: If your video composition is missing required tracks (like a video track with valid timing), the save operation will fail silently with error -1.

3. Race Conditions or Authorization Issues #

Even if your base code works, modifying the image can introduce asynchronous timing problems:

• Unfinished Media Preparation: If you kick off the PHPhotoLibrary save operation before your textToImage rendering is fully complete, you're trying to save incomplete data.
• Stale Authorization Status: Rarely, the Photos authorization might have changed (e.g., user revoked and re-enabled it mid-session) without your code checking it again before saving.

Fix: Always re-verify authorization status right before the save call, and ensure all image processing finishes synchronously before initiating the library save.

4. Memory Overload During Processing #

Large original images combined with text rendering can spike memory usage, leading to corrupted video output:

• If your source image is 4K+ resolution, rendering text on it without scaling first can cause memory pressure, which might corrupt the video data being passed to PHPhotoLibrary.

Fix: Downscale your original image to a reasonable size (e.g., match the device's screen resolution) before adding text.

内容的提问来源于stack exchange，提问作者Alex Stone