siyuan-note/siyuan · error

ErrInputTooLarge

ErrInputTooLarge

Error message

HEIF image exceeds the input size limit

What it means

ErrInputTooLarge (kernel/heif/convert.go:52) is returned when a HEIF input exceeds MaxInputBytes = 32 MiB (convert.go:38). It is enforced at every entry point: convert (convert.go:105), ImageSize (158), ReadFileLimited (69/81 when reading the asset from disk), and cache GetOrCreate (cache.go:97). The cap bounds decoder memory; encrypted assets get a 2 MiB ciphertext margin when read (serve.go reads MaxInputBytes + 2 MiB).

Source

Thrown at kernel/heif/convert.go:52

const (
	thumbnailWidth   = 520
	previewQuality   = 90
	thumbnailQuality = 85
	MaxInputBytes    = 32 * 1024 * 1024
	maxDimension     = 65535
	desktopMaxPixels = 50_000_000
	mobileMaxPixels  = 12_500_000
	// 解码层仅接受至多 10-bit 4:2:0、无透明通道的单 slice 图像；这里按解码面、CTU 表、
	// NRGBA 和一次合并变换预留每像素 16 字节，再单独预留源文件、RBSP 副本与 JPEG 输出。
	workingBytesPerPixel = 16
	desktopWorkingBudget = 960 * 1024 * 1024
	mobileWorkingBudget  = 320 * 1024 * 1024
	desktopOutputReserve = 96 * 1024 * 1024
	mobileOutputReserve  = 32 * 1024 * 1024
)

var (
	ErrInputTooLarge = errors.New("HEIF image exceeds the input size limit")
	ErrImageTooLarge = errors.New("HEIF image exceeds the dimension limit")
	ErrInvalidMode   = errors.New("invalid HEIF conversion mode")

	conversionSlots = make(chan struct{}, 1)
	maxPixels       = platformMaxPixels()
)

func platformMaxPixels() int {
	if runtime.GOOS == "android" || runtime.GOOS == "ios" {
		return pixelsWithinBudget(mobileWorkingBudget, mobileOutputReserve, mobileMaxPixels)
	}
	return pixelsWithinBudget(desktopWorkingBudget, desktopOutputReserve, desktopMaxPixels)
}

func ReadFileLimited(path string, maxBytes int64) ([]byte, error) {
	if maxBytes <= 0 {
		return nil, ErrInputTooLarge
	}

View on GitHub (pinned to afa823b6b4)

Solutions

1. Re-export/compress the photo below 32 MiB (lower HEIF quality or reduce resolution)
2. Convert the image to JPEG before inserting - the original is still stored as a plain asset, only HEIF preview generation is refused
3. Prefer JPEG for very large captures, especially on mobile

Example fix

# before: insert photo_50mp_lossless.heic (40 MiB)
# -> HEIF image exceeds the input size limit

# after: re-encode below 32 MiB, then insert
magick photo_50mp_lossless.heic -quality 80 photo_small.heic

// Go: skip preview generation for oversized assets
if fi, err := os.Stat(assetPath); err == nil && fi.Size() > int64(heif.MaxInputBytes) {
    return nil // serve the original file as-is, skip HEIF preview
}

func isHEIFInputTooLarge(err error) bool {
    return errors.Is(err, heif.ErrInputTooLarge)
}

When it happens

Trigger: Inserting a .heic/.heif larger than 33554432 bytes; the preview pipeline (serve.go:1215/1255) reading such an asset; calling heif.ImageSize on oversized data (model/assets.go:69).

Common situations: High-megapixel phone HEIFs saved at near-lossless quality; panorama or burst exports; photos re-saved losslessly by editors pushing past 32 MiB.

Understand the failure class

Background: "File too large" / "file size exceeds limit" errors: why libraries cap file sizes and how to fix them — this error's family across 46 libraries.

Related errors

• ErrImageTooLarge
• empty HEIF image
• Agent capability name and description are required
• source is not an encrypted asset
• invalid asset type [%s]

AI-assisted analysis of siyuan-note/siyuan@afa823b6b4 (2026-08-18). Data as JSON: /api/errors/a3bb405397d79493. Report an issue: GitHub.