Tess4J：如何使用 ResultIterator？答案

【问题标题】：Tess4J: How to use ResultIterator?Tess4J：如何使用 ResultIterator？
【发布时间】：2013-02-10 03:57:41
【问题描述】：

我正在将我的 OCR 应用程序从 c++ 转换为 java。使用 Tess4J 我想获得每个单词的边界框。但是，显然 TessResultIterator 没有提供任何方法。所以我想是否有可能以某种方式获取这些数据？

这是我当前的代码：

TessBaseAPI api = TessAPI1.TessBaseAPICreate();
TessAPI1.TessBaseAPIInit3(api, path, lang);
TessAPI1.TessBaseAPISetPageSegMode(api, TessAPI1.TessPageSegMode.PSM_AUTO);
TessAPI1.TessBaseAPISetImage(api, img, w, h, bpp, bpp*w);
TessAPI1.TessBaseAPIGetUTF8Text(api);
TessResultIterator it = TessAPI1.TessBaseAPIGetIterator(api);

在 c++ 中我可以这样继续：

char* text = it->GetUTF8Text(tesseract::RIL_WORD); 
int left, top, right, bttm;
it->BoundingBox(tesseract::RIL_WORD, &left, &top, &right, &bttm);

【问题讨论】：

标签： java ocr tesseract

【解决方案1】：

你可以试试下面的代码sn-p吗？我并没有真正彻底地测试它。

TessResultIterator ri = TessAPI1.TessBaseAPIGetIterator(api);
TessPageIterator pi = TessAPI1.TessResultIteratorGetPageIterator(ri);
String str = TessAPI1.TessResultIteratorGetUTF8Text(ri, TessPageIteratorLevel.RIL_WORD);
IntBuffer leftB = IntBuffer.allocate(1);
IntBuffer topB = IntBuffer.allocate(1);
IntBuffer rightB = IntBuffer.allocate(1);
IntBuffer bottomB = IntBuffer.allocate(1);
TessAPI1.TessPageIteratorBoundingBox(pi, TessPageIteratorLevel.RIL_WORD, leftB, topB, rightB, bottomB);
int left = leftB.get();
int top = topB.get();
int right = rightB.get();
int bottom = bottomB.get();

【讨论】：

【解决方案2】：

以下方法取自GitHub page for Tess4J，它展示了如何迭代输入文档中每个匹配词的边界框。让这个代码适应你自己的需要应该很容易，例如通过使用您自己的 Tesseract 数据目录路径以及您自己的图像文件的路径。

public void testResultIterator() throws Exception {
    File tiff = new File(this.testResourcesDataPath, "eurotext.tif");
    BufferedImage image = ImageIO.read(new FileInputStream(tiff));
    ByteBuffer buf = ImageIOHelper.convertImageData(image);
    int bpp = image.getColorModel().getPixelSize();
    int bytespp = bpp / 8;
    int bytespl = (int) Math.ceil(image.getWidth() * bpp / 8.0);
    TessAPI1.TessBaseAPIInit3(handle, datapath, language);
    TessAPI1.TessBaseAPISetPageSegMode(handle, TessPageSegMode.PSM_AUTO);
    TessAPI1.TessBaseAPISetImage(handle, buf, image.getWidth(), image.getHeight(), bytespp, bytespl);
    ETEXT_DESC monitor = new ETEXT_DESC();
    ITessAPI.TimeVal timeout = new ITessAPI.TimeVal();
    timeout.tv_sec = new NativeLong(0L); // time > 0 causes blank ouput
    monitor.end_time = timeout;
    TessAPI1.TessBaseAPIRecognize(handle, monitor);
    TessResultIterator ri = TessAPI1.TessBaseAPIGetIterator(handle);
    TessPageIterator pi = TessAPI1.TessResultIteratorGetPageIterator(ri);
    TessAPI1.TessPageIteratorBegin(pi);
    int level = TessPageIteratorLevel.RIL_WORD;

    do {
        Pointer ptr = TessAPI1.TessResultIteratorGetUTF8Text(ri, level);
        String word = ptr.getString(0);
        TessAPI1.TessDeleteText(ptr);
        float confidence = TessAPI1.TessResultIteratorConfidence(ri, level);
        IntBuffer leftB = IntBuffer.allocate(1);
        IntBuffer topB = IntBuffer.allocate(1);
        IntBuffer rightB = IntBuffer.allocate(1);
        IntBuffer bottomB = IntBuffer.allocate(1);
        TessAPI1.TessPageIteratorBoundingBox(pi, level, leftB, topB, rightB, bottomB);
        int left = leftB.get();
        int top = topB.get();
        int right = rightB.get();
        int bottom = bottomB.get();
        System.out.print(String.format("%s %d %d %d %d %f", word, left, top, right, bottom, confidence));

        IntBuffer boldB = IntBuffer.allocate(1);
        IntBuffer italicB = IntBuffer.allocate(1);
        IntBuffer underlinedB = IntBuffer.allocate(1);
        IntBuffer monospaceB = IntBuffer.allocate(1);
        IntBuffer serifB = IntBuffer.allocate(1);
        IntBuffer smallcapsB = IntBuffer.allocate(1);
        IntBuffer pointSizeB = IntBuffer.allocate(1);
        IntBuffer fontIdB = IntBuffer.allocate(1);
        String fontName = TessAPI1.TessResultIteratorWordFontAttributes(ri, boldB, italicB, underlinedB,
                monospaceB, serifB, smallcapsB, pointSizeB, fontIdB);
        boolean bold = boldB.get() == TRUE;
        boolean italic = italicB.get() == TRUE;
        boolean underlined = underlinedB.get() == TRUE;
        boolean monospace = monospaceB.get() == TRUE;
        boolean serif = serifB.get() == TRUE;
        boolean smallcaps = smallcapsB.get() == TRUE;
        int pointSize = pointSizeB.get();
        int fontId = fontIdB.get();
        System.out.println(String.format("  font: %s, size: %d, font id: %d, bold: %b,"
                + " italic: %b, underlined: %b, monospace: %b, serif: %b, smallcap: %b", fontName, pointSize,
                fontId, bold, italic, underlined, monospace, serif, smallcaps));
    } while (TessAPI1.TessPageIteratorNext(pi, level) == TRUE);
}

上述脚本的输出将是一些行数，每个匹配的单词一行，看起来像这样：

SOME_WORD 65 60 120 83 96.072098 字体：null，大小：32，字体 id：-1，粗体：false，斜体：false，下划线：false，等宽：false，serif：false，smallcap：false

匹配单词SOME_WORD 之后的前四个数字是左、上、右和下坐标。接下来是置信度，以百分比形式给出。然后，还有一些关于文本本身的元数据，包括字体样式信息。

【讨论】：