API Reference

API Reference

Package dev.ffmpegkit.tesseract.

TesseractOCR

The main entry point. One instance holds one native engine.

Member	Signature	Notes
isInitialized	val: Boolean	True between initialize and release.
initialize	suspend (context, language = "eng", config = TesseractConfig())	Extracts tessdata, starts engine.
recognize	suspend (bitmap: Bitmap): TesseractResult	OCR a bitmap.
recognizeFile	suspend (path: String): TesseractResult	Decode + OCR an image file.
addLanguage	suspend (context, language, file: File)	Register a downloaded traineddata.
getAvailableLanguages	(context): List<String>	Codes on disk.
getVersion	(): String	Native Tesseract version, e.g. "5.5.0".
release	()	Free native memory. Safe to call twice.

val ocr = TesseractOCR()
ocr.initialize(context, "eng")
val r = ocr.recognize(bitmap)
ocr.release()

Threading

suspend functions run on a background dispatcher internally. A single instance is not thread-safe — don't call recognize concurrently on the same instance.

TesseractConfig

data class TesseractConfig(
    val pageSegMode: Int = 3,            // PSM — 3 = auto layout
    val ocrEngineMode: Int = 3,          // OEM — 3 = default (LSTM)
    val whitelistChars: String = "",     // restrict to these chars, e.g. "0123456789"
    val preserveInterwordSpaces: Boolean = false,
)

Common PSM values: 3 auto, 6 single uniform block, 7 single line, 10 single character. Pass a config to initialize:

ocr.initialize(context, "eng", TesseractConfig(pageSegMode = 7))

TesseractResult

data class TesseractResult(
    val text: String,                 // full recognised text
    val confidence: Int,              // mean confidence 0–100
    val words: List<TesseractWord>,   // per-word detail
    val processingTimeMs: Long,       // recognition wall time
)

data class TesseractWord(
    val text: String,
    val confidence: Int,
    val boundingBox: android.graphics.Rect,   // pixel coords in the source image
)

TesseractException

Sealed type; subtypes:

• LanguageDataMissing(language) — traineddata absent; bundle it or addLanguage.
• InitFailed(dataPath, language) — native Init() failed.
• NotInitialized — OCR called before initialize / after release.
• InvalidImage(message) — image could not be decoded/read.