场景文本图像超分辨率(Scene Text Image Super-Resolution,STISR)旨在提高文本在低分辨率图像中的分辨率和可读性.但是在空间变形或低分辨率的文本图像中,由于缺乏文本区域细节,语义线索和视觉特征信息难以与字符位置匹配对齐,文本识别效果不佳.针对该问题,本文提出多域字符距离感知的场景文本图像超高分辨率重建方法(Perceiving Multi-Domain Character distance super-resolution,PMDC),强化视觉语义特征,提高文本区域和纹理信息.首先,采用非对称卷积以及语义先验信息模块,提取文本图像的视觉和语义特征信息;其次,融合字符距离感知模块中的视觉和语义特征,得到增强位置编码感知字符间的间距变化和语义相似性;最后,结合引导线索和视觉特征对像素进行重组得到超分辨率文本图像.在公开数据集TextZoom上的实验结果,与最近TATT文本超分网络性能相比,在峰值信噪比指标上提高0.11 dB,有效提高文本清晰度和边缘纹理细节,同时提升1.5%的平均识别准确率,改进文本图像的可读性.
Scene Text Image Super-Resolution Reconstruction Based on Perceiving Multi-Domain Character Distance
Scene text image super-resolution (STISR) aims to enhance the resolution and legibility of text in low-reso-lution images. In cases of spatial deformation or low-resolution text images,the lack of details in text regions and the diffi-culty in aligning semantic cues and visual features with character position make it difficult to recognize text effectively. In order to address these challenges,this paper proposes a perceiving multi-domain character distance for scene text image su-per-resolution method (PMDC),which improves the image text region and edge texture details. Firsly,the visual and seman-tic features are extracted by using the asymmetric convolution module along with the semantic prior module. Then the en-hanced position coding is obtained by the character distance perception module to perceive the distance change and seman-tic similarity between characters. Finally,the guiding cues and visual features are combined to restructure the pixels and generate a super-resolution text image. In comparison to TATT,experimental results from the public dataset TextZoom showed an increase of 0.11 dB in the fidelity of the peak signal-to-noise ratio index. This improvement effectively enhances the clarity of the text area and the detailed edge texture. Additionally,the recognition accuracy was improved by 1.4%,which effectively enhances the readability of the text image.
computer visionscene text imagessuper-resolutionattention mechanismfeature information association