Sectionalized image decoding method

The invention discloses a method for segmenting and decoding an image, which comprises the following steps: (1) an internal memory with a side of an MCU row is firstly distributed in the internal memory; the image to be decoded is divided into more than two MCU rows and then height and width of the image to be decoded is initialized to obtain a reduction factor; (2) one of the MCU rows divided bythe step (1) is taken out in sequence to correspondingly generate YUV data of the MCU row; (3) the YUV data of the MCU row generated by the step (2) is reduced and sampled by using the reduction factorof the step (1) so as to be converted into RGB data and then the RGB data is stored in a target buffering position; (4) the internal memory distributed in the step (1) is repeatedly used and the step (2) and (3) are repeated in turn for other divided MCU rows of the image until the decoding of the whole image is finished; (5) the decoded whole image is buffered and sent to a display screen to bed isplayed. The method for segmenting and decoding the image avoids requirement for using a large internal memory and achieves an equal effect without affecting the original speed.