处理期间TessAPI错误。在Spring Mvc和tomcat 7中

Question

我在Spring MVC中使用Tesseract ocr来转换一些可搜索的pdf文件中的图像。

我使用了tessApi和tessrenderresult，它在简单的java项目中运行得非常好。但是，当我在tomcat 7中部署它时，它在Spring MVC项目中不起作用。我遇到了错误：

int result = api.TessBaseAPIProcessPages1(handle, imagepath, null, 0,
                renderer);

我正在接受以下异常

Error during processing.

以下是我的代码：

public class ImageToPDF {

    private static String datapath = "F:/Projects Dev/Pfe Projects/GedWeb/.";
    private static String language = "fra";
    private static TessAPI api;
    private static TessBaseAPI handle;

    public ImageToPDF() {
        super();

        api = new TessDllAPIImpl().getInstance();
        handle = api.TessBaseAPICreate();

    }

    public void finalize() throws Throwable {

        super.finalize();
    }

    public void convert(String imagepath) {
        File file = new File(imagepath);
        String nomfile = FilenameUtils.removeExtension(file.getName());
        String parentfolder = file.getParent();
        String output = parentfolder + File.separator + nomfile + ".txt";
        int set_only_init_params = FALSE;
        int oem = TessOcrEngineMode.OEM_DEFAULT;
        PointerByReference configs = null;
        int configs_size = 0;
        String[] params = { "load_system_dawg", "tessedit_char_whitelist" };
        String vals[] = { "Relevé", "" }; // 0123456789-.IThisalotfpnex
        PointerByReference vars_vec = new PointerByReference();
        vars_vec.setPointer(new StringArray(params));
        PointerByReference vars_values = new PointerByReference();
        vars_values.setPointer(new StringArray(vals));
        NativeSize vars_vec_size = new NativeSize(params.length);
        api.TessBaseAPISetOutputName(handle, output);

        int rc = api.TessBaseAPIInit4(handle, datapath, language, oem, configs,
                configs_size, vars_vec, vars_values, vars_vec_size,
                set_only_init_params);
        System.out.println(rc);
        if (rc != 0) {
            api.TessBaseAPIDelete(handle);
            System.err.println("Could not initialize tesseract.");
            return;
        }
        TessResultRenderer renderer = api.TessHOcrRendererCreate();
        api.TessResultRendererInsert(renderer, api.TessBoxTextRendererCreate());
        api.TessResultRendererInsert(renderer, api.TessTextRendererCreate());
        String dataPath = api.TessBaseAPIGetDatapath(handle);

        api.TessResultRendererInsert(renderer,
                api.TessPDFRendererCreate(dataPath));
        api.TessResultRendererBeginDocument(renderer, imagepath);
        int result = api.TessBaseAPIProcessPages1(handle, imagepath, null, 0,
                renderer);
        api.TessResultRendererEndDocument(renderer);
        System.out.println(handle.toString());
        System.out.println(renderer.toString());
        if (result == FALSE) {
            System.err.println("Error during processing.");
            return;
        }
        File file1 = new File(imagepath);
        String parent = file1.getParent();
        String nomfile1 = FilenameUtils.removeExtension(file1.getName());
        String outputbase = parent + File.separator + nomfile1;
        for (; renderer != null; renderer = api
                .TessResultRendererNext(renderer)) {
            String ext = api.TessResultRendererExtention(renderer).getString(0);
            System.out
                    .println(String
                            .format("TessResultRendererExtention: %s\nTessResultRendererTitle: %s\nTessResultRendererImageNum: %d",
                                    ext, api.TessResultRendererTitle(renderer)
                                            .getString(0),
                                    api.TessResultRendererImageNum(renderer)));

            PointerByReference data = new PointerByReference();
            IntByReference dataLength = new IntByReference();
            result = api
                    .TessResultRendererGetOutput(renderer, data, dataLength);
            if (result == TRUE) {
                if (ext.equals("pdf")) {
                    int length = dataLength.getValue();
                    byte[] bytes = data.getValue().getByteArray(0, length);
                    try {
                        File file3 = new File(outputbase + "." + ext);

                        // create parent dirs when necessary
                        if (file3.getParentFile() != null) {
                            file3.getParentFile().mkdirs();
                        }

                        FileOutputStream bw = new FileOutputStream(
                                file3.getAbsoluteFile());
                        bw.write(bytes);
                        bw.close();
                    } catch (IOException e) {
                        e.printStackTrace();
                    }
                } else {
                    String result1 = data.getValue().getString(0);
                }
            }
        }

        api.TessDeleteResultRenderer(renderer);
        api.TessBaseAPIDelete(handle);

    }

}

有什么建议吗？