Image sparsity cannot be fully exploited through either whole or fixed block sampling during image compressive sensing(CS). An insurmountable discrepancy is observed between sampling rate and image reconstruction quality. This study proposes an adaptive block compressive sensing(ABCS) algorithm based on the changes of image texture. The algorithm combines JPEG quantization methods and reduces the sampling rate to increase the compression ratio without reducing the quality of the premise of image reconstruction. The proposed ABCS algorithm requires that the image be roughly divided into blocks for starters. Then

the texture complexity of each block is calculated and analyzed to select the optimal sampling rate in the CS process. Whether a block should be further divided depends on whether its texture complexity is higher or lower than the corresponding threshold. When the texture complexity is lower than the corresponding threshold

the optimal sampling rate should be selected to apply compressive sampling. When the texture complexity is higher than the corresponding threshold

the block should be further divided into even smaller blocks. The process is repeated until the block size is 16×16. After the division

if the texture complexity is still higher than the maximum corresponding threshold

then JPEG quantization coding should be applied. The new compression algorithms are generated by combining the ABCS and typical CS reconstruction algorithms. Experiments were conducted to compare the new algorithms and the original algorithms. Under the condition of similar sampling rate

the quality of the reconstructed image is evidently improved

particularly at a low sampling rate. For example

the peak signal-to-noise ratio of the reconstructed image is approximately 30 dB at 20% sampling rate. Simulation results show that adaptive block sampling makes full use of the sparsity of the image and improves the efficiency of compressed sensing. The blocks using JPEG encoding avoid poor-quality reconstruction of the complex texture area and reduce the reconstruction time.