A method for coding a depth map using simplified depth coding SDC, wherein the method comprises: determining a size of an image block of the depth map and a maximum prediction size, wherein the image block is a transform block and is represented by TrafoSize × TrafoSize pixels, TrafoSize is a positive integer number, the size of the image block is a size of the transform block and is represented by TrafoSize, and the maximum prediction size is a maximum transform size; determining an intra prediction mode, wherein the intra prediction mode is a depth modeling mode, DMM, or a planar mode or a direct current mode; comparing the size of the image block with the maximum prediction size; when the size of the image block is greater than the maximum prediction size, splitting the image block to obtain N split image blocks according to the size of the image block and the maximum prediction size, wherein a size of the N split image blocks is the same as the maximum prediction size and the N split image blocks are all transform blocks; and determining an average value of prediction data of each of the N split image blocks by using the intra prediction mode and by using the following formula: PV i = ∑ PPi x i x, y / sumOfPPix, wherein PV i is an average value of prediction data of the i th image block among the N split image blocks, PPix i [ x, y] is a pixel value in prediction data whose coordinates are [ x, y] in the i th image block, and sumOfPPix is the number of pixels in the i th image block; determining an average value of raw data of each of the N split image blocks; determining residuals of the N split image blocks according to the average value of the prediction data of each of the N split image blocks and the average value of the raw data of each of the N split image blocks; and coding the residuals of the N split image blocks, so as to complete performing simplified depth coding SDC on the N split image blocks. determining a size of an image block of the depth map and a maximum prediction size, wherein the image block is a transform block and is represented by TrafoSize × TrafoSize pixels, TrafoSize is a positive integer number, the size of the image block is a size of the transform block and is represented by TrafoSize, and the maximum prediction size is a maximum transform size; determining an intra prediction mode, wherein the intra prediction mode is a depth modeling mode, DMM, or a planar mode or a direct current mode; comparing the size of the image block with the maximum prediction size; when the size of the image block is greater than the maximum prediction size, splitting the image block to obtain N split image blocks according to the size of the image block and the maximum prediction size, wherein a size of the N split image blocks is the same as the maximum prediction size and the N split image blocks are all transform blocks; and determining an average value of prediction data of each of the N split image blocks by using the intra prediction mode and by using the following formula: PV i = ∑ PPi x i x, y / sumOfPPix, wherein PV i is an average value of prediction data of the i th image block among the N split image blocks, PPix i [ x, y] is a pixel value in prediction data whose coordinates are [ x, y] in the i th image block, and sumOfPPix is the number of pixels in the i th image block; determining an average value of raw data of each of the N split image blocks; determining residuals of the N split image blocks according to the average value of the prediction data of each of the N split image blocks and the average value of the raw data of each of the N split image blocks; and coding the residuals of the N split image blocks, so as to complete performing simplified depth coding SDC on the N split image blocks.