I'm new to the forum and have a question about JPEG compression. I coded the C-code from the JPEG software group version 8d released on 15/1/12, in Mathworks Simulink. When I run the code on a video sequence and look at the meta data for each compressed frame, saved as a jpeg file, some show Baseline DCT encoding and some Extended DCT encoding. I set the Encoding to the DCT_DEFAULT so I assumed that it would use the same encoding on all frames. There is very little difference in the image content when this switch occurs. Does anyone know why it switches bewteen the two and if so how do I stop it and force it to just use the baseline encoding?