Image CAPTCHA Mengembalikan Jawaban Salah: Optimasi Kualitas

Jika CaptchaAI mengembalikan jawaban yang salah untuk image CAPTCHA, masalahnya hampir selalu ada pada gambar yang dikirimkan — bukan solver-nya. Berikut cara mendiagnosa dan memperbaikinya.

Penyebab Umum Jawaban Salah

Solusi 1: Verifikasi Kualitas Gambar Sebelum Submit

import base64
from io import BytesIO
from PIL import Image


def validate_captcha_image(image_path):
    """Check image quality before submitting to CaptchaAI."""
    img = Image.open(image_path)
    width, height = img.size
    issues = []

    # Minimum resolution
    if width < 50 or height < 20:
        issues.append(f"Too small: {width}x{height}px (min 50x20)")

    # Check if mostly blank
    pixels = list(img.getdata())
    if img.mode == "RGB":
        white_count = sum(1 for p in pixels if p[0] > 250 and p[1] > 250 and p[2] > 250)
    else:
        white_count = sum(1 for p in pixels if p > 250)

    blank_ratio = white_count / len(pixels)
    if blank_ratio > 0.95:
        issues.append(f"Image appears blank ({blank_ratio:.0%} white)")

    # File size check
    img_bytes = BytesIO()
    img.save(img_bytes, format="PNG")
    size_kb = img_bytes.tell() / 1024
    if size_kb < 1:
        issues.append(f"File too small ({size_kb:.1f} KB) — may be empty")
    if size_kb > 600:
        issues.append(f"File too large ({size_kb:.0f} KB) — submit under 600 KB")

    return issues


issues = validate_captcha_image("captcha.png")
if issues:
    for issue in issues:
        print(f"WARNING: {issue}")
else:
    print("Image quality OK")

Solusi 2: Encoding Base64 yang Benar

import base64


def encode_captcha(image_path):
    """Properly encode a CAPTCHA image to base64."""
    with open(image_path, "rb") as f:
        raw = f.read()

    encoded = base64.b64encode(raw).decode("ascii")

    # Verify round-trip
    decoded = base64.b64decode(encoded)
    assert decoded == raw, "Base64 encoding corrupted the image"

    return encoded


# WRONG — encoding a file path string
bad = base64.b64encode(b"captcha.png").decode()  # Encodes filename, not image!

# CORRECT — encoding file contents
with open("captcha.png", "rb") as f:
    good = base64.b64encode(f.read()).decode()

Solusi 3: Preprocessing Gambar

from PIL import Image, ImageFilter, ImageEnhance
from io import BytesIO
import base64


def preprocess_captcha(image_path):
    """Improve image quality for better OCR accuracy."""
    img = Image.open(image_path)

    # Convert to RGB if needed
    if img.mode != "RGB":
        img = img.convert("RGB")

    # Upscale small images
    width, height = img.size
    if width < 200:
        scale = 200 / width
        img = img.resize(
            (int(width * scale), int(height * scale)),
            Image.LANCZOS,
        )

    # Increase contrast
    enhancer = ImageEnhance.Contrast(img)
    img = enhancer.enhance(1.5)

    # Sharpen
    img = img.filter(ImageFilter.SHARPEN)

    # Convert to PNG bytes
    buffer = BytesIO()
    img.save(buffer, format="PNG")
    return base64.b64encode(buffer.getvalue()).decode()

Solusi 4: Tambahkan Hint Tipe dan Bahasa

import requests


def solve_image(api_key, image_base64, **hints):
    """Submit image CAPTCHA with quality hints."""
    data = {
        "key": api_key,
        "method": "base64",
        "body": image_base64,
        "json": 1,
    }

    # Add optional hints for better accuracy
    if "language" in hints:
        data["language"] = hints["language"]  # 0=default, 1=Cyrillic, 2=Latin
    if "textinstructions" in hints:
        data["textinstructions"] = hints["textinstructions"]
    if "numeric" in hints:
        data["numeric"] = hints["numeric"]  # 1=digits only, 2=letters only
    if "min_len" in hints:
        data["min_len"] = hints["min_len"]
    if "max_len" in hints:
        data["max_len"] = hints["max_len"]

    resp = requests.post("https://ocr.captchaai.com/in.php", data=data, timeout=30)
    return resp.json()


# Example: Digits-only CAPTCHA, 4-6 characters
result = solve_image(
    "YOUR_API_KEY",
    encoded_image,
    numeric=1,
    min_len=4,
    max_len=6,
)

# Example: Case-sensitive text
result = solve_image(
    "YOUR_API_KEY",
    encoded_image,
    textinstructions="Case-sensitive, enter exactly as shown",
)

Solusi 5: Ambil Elemen CAPTCHA Secara Penuh

from selenium import webdriver
from selenium.webdriver.common.by import By
import base64


def capture_captcha_element(driver, selector):
    """Screenshot only the CAPTCHA element, not the full page."""
    element = driver.find_element(By.CSS_SELECTOR, selector)

    # Element screenshot (better than page crop)
    png_bytes = element.screenshot_as_png

    # Verify it's not empty
    if len(png_bytes) < 500:
        raise ValueError("Screenshot too small — element may not be visible")

    return base64.b64encode(png_bytes).decode()


# Usage
driver = webdriver.Chrome()
driver.get("https://example.com")
image_b64 = capture_captcha_element(driver, "img#captchaImage")

Solusi 6: Tangani CAPTCHA Dynamic/Rotating

import time


def solve_with_fresh_image(driver, api_key, captcha_selector):
    """Capture and solve CAPTCHA immediately to avoid expiry."""
    # Wait for CAPTCHA to load fully
    time.sleep(2)

    # Capture fresh
    element = driver.find_element(By.CSS_SELECTOR, captcha_selector)
    png_bytes = element.screenshot_as_png
    body = base64.b64encode(png_bytes).decode()

    # Submit immediately
    resp = requests.post("https://ocr.captchaai.com/in.php", data={
        "key": api_key,
        "method": "base64",
        "body": body,
        "json": 1,
    }, timeout=30)
    result = resp.json()

    if result.get("status") != 1:
        raise RuntimeError(result.get("request"))

    task_id = result["request"]

    # Poll — image CAPTCHAs solve fast
    time.sleep(5)
    for _ in range(12):
        resp = requests.get("https://ocr.captchaai.com/res.php", params={
            "key": api_key, "action": "get",
            "id": task_id, "json": 1,
        }, timeout=15)
        data = resp.json()

        if data.get("status") == 1:
            return data["request"]
        if data["request"] != "CAPCHA_NOT_READY":
            raise RuntimeError(data["request"])
        time.sleep(3)

    raise TimeoutError("Image solve timeout")

Daftar Periksa Pemecahan Masalah

Pertanyaan Umum

Seberapa akurat CaptchaAI untuk image CAPTCHA?

Dengan gambar yang di-submit dengan benar, CaptchaAI mendukung 27.500+ tipe CAPTCHA dengan akurasi tinggi. Sebagian besar kegagalan disebabkan kualitas gambar yang buruk atau parameter yang salah.

Haruskah saya preprocessing gambar sebelum submit?

Hanya jika gambar aslinya berkualitas rendah. CaptchaAI menangani gambar CAPTCHA standar dengan baik tanpa preprocessing. Upscaling gambar yang sangat kecil dan meningkatkan kontras bisa membantu mengatasi masalah.

Bisakah saya melaporkan jawaban yang salah?

Ya. Gunakan endpoint reportbad dengan task ID untuk melaporkan jawaban yang salah. Ini membantu meningkatkan akurasi dan dapat mengkredit akun Anda.

Panduan Terkait

• Diagnosa Success Rate CAPTCHA yang Menurun