I am trying to convert PNG image file to text using pytesseract. It is giving me the below error.
TesseractError: (1, '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.')
When i do tesseract -v
tesseract 3.05.00dev
 leptonica-1.72
  libjpeg 9 : libpng 1.5.14 : libtiff 4.0.3 : zlib 1.2.5 : libopenjp2 2.1.0
I also meet this problem, and I can't find the answer on the internet.
But I try to download the tesseract-ocr and install it, then:

set environment variable, TESSDATA_PREFIX:"C:\Program Files (x86)\Tesseract-OCR\tessdata"
add C:\Program Files (x86)\Tesseract-OCR to the path variable.
edit pytesseract.py in Line 35, tesseract_cmd = 'C:\\Program Files (x86)\\Tesseract-OCR\\tesseract.exe'

When I call pytesseract.image_to_string(img) in anaconda prompt, it return a string. My Environment：

pytesseract 0.2.6
pillow 5.2.0
tesseract 4.00.00alpha
Tesseract Open Source OCR Engine v3.05.00dev with Leptonica Warning in pixReadMemPng