当我通过运行以下命令尝试使用tesseract-OCR时：tesseract img.png out 我明白了：
Tesseract Open Source OCR Engine v3.05.00dev with Leptonica
Warning in pixReadMemPng: work-around: writing to a temp file
libpng warning: Application built with libpng-1.4.3 but running with 1.5.14
Error in pixReadStreamPng: png_ptr not made
Error in pixReadMemPng: pix not read
Error in pixReadMem: png: no pix returned
Error during processing.