Question

我正在使用AmazonTextract .NET SDK从图像中提取文本。其返回的块列表作为响应的一部分。我需要从提取的文本中提取键值对。我想我们需要遍历阻止列表，检查KEY_VALUE_SET

我的理解正确吗？有人可以给我一段代码，在提取文本后为我提供键值对。

我的示例代码：

    var DocRequest = new AnalyzeDocumentRequest()
    {
       Document = MyDocument,
       FeatureTypes = new List<string> { Amazon.Textract.FeatureType.FORMS, Amazon.Textract.FeatureType.TABLES }
    };
    var response = client.AnalyzeDocumentAsync(DocRequest);

Answer 1

以下代码用于填充地图。 AnalyzeResult 类只是键和值映射以及页面列表的持有者。

       List<Block> blocks = result.getBlocks();
        for (Block block : blocks) {
            String blockId = block.getId();
            analyzeResult.blockMap.put(blockId, block);
            String blockType = block.getBlockType();
            switch(blockType){
                case AppConstant.BLOCK_PAGE :
                    page = new ArrayList<TextLine>();
                    analyzeResult.pages.add(page);
                    break;
                case AppConstant.BLOCK_KEY_VALUE_SET :
                    if (block.getEntityTypes().contains(AppConstant.BLOCK_KEY)) {
                        analyzeResult.keyMap.put(blockId, block);
                    }
                    else {
                        analyzeResult.valueMap.put(blockId, block);
                    }
                    break;
                
            }
        }


        paginationToken = result.getNextToken();
        if (paginationToken == null) {
            finished = true;
        }
    }

以下函数可用于获取关系和查找键值对

public List getKVRelationShip(AnalyzeResult analyzeResult) {

    List listOfFormFields = new ArrayList<FormInfo>();
    final Set<Map.Entry<String, Block>> entries = analyzeResult.keyMap.entrySet();
    for (Map.Entry<String, Block> entry : entries) {
        Block keyBlock = entry.getValue();
        Block valueBlock = this.findValueBlock(keyBlock, analyzeResult.valueMap);
        if(valueBlock != null){
            String key = getText(keyBlock, analyzeResult.blockMap);
            String val = getText(valueBlock, analyzeResult.blockMap);
            key = key != null ? key.trim() : "";
            val = val != null ? val.trim() : "";
            FormInfo formInfo = new FormInfo(key, val, keyBlock.getPage(),
                    keyBlock.getGeometry().getBoundingBox().getTop(), keyBlock.getConfidence());
            listOfFormFields.add(formInfo);
        }
    }
    Collections.sort(listOfFormFields);
    return listOfFormFields;
}

public String getText(Block results, Map blockMap) {
    String text = "";
    if (results.getRelationships() != null  && results.getRelationships().size() != 0) {
        for (Relationship relationship : results.getRelationships()) {
            if (relationship.getType().equals(AppConstant.BLOCK_CHILD)) {
                for (String childId : relationship.getIds()) {
                    Block word = (Block) blockMap.get(childId);
                    if (word.getBlockType().equals(AppConstant.BLOCK_WORD)) {
                        text = text + word.getText() + " ";
                    }
                    if (word.getBlockType().equals(AppConstant.BLOCK_SELECTION_ELEMENT)) {
                        if (word.getSelectionStatus().equals(AppConstant.BLOCK_SELECTED)) {
                            text = text + "X";
                        }
                    }
                }
            }
        }
    }
    return text;
}

private Block findValueBlock(Block block, Map valueMap) {
    Block valueBlock = null;
    for (Relationship relationship : block.getRelationships()) {
        if (relationship.getType().equals(AppConstant.BLOCK_VALUE)) {
            for (String valueId : relationship.getIds()) {
                valueBlock = (Block) valueMap.get(valueId);
            }
        }
    }
    return valueBlock;
}

Answer 2

AWS在其文档中提供了用于键值映射的python示例代码。它并不十分复杂。您可以尝试了解python代码背后的逻辑，然后在您的.NET项目中实现它。

以下是映射代码：https://docs.aws.amazon.com/textract/latest/dg/examples-extract-kvp.html

Amazon Textract-如何提取键值对

2 个答案: