dsp解壓縮

IAR版本

I have written a simple program for the STM32F4 Discovery board that plays a short mp3 file flash memory. For the decoding, the fixed point version of the Helix mp3 decoder is used. The audio output driver is the one used for the Peridiummmm demo, modified to use the peripheral library provided by ST.



The audio driver has two DMA buffers and a callback function that asks a user-provided function to fill one buffer with audio data when it runs out, while the other DMA buffer is streamed to the audio CODEC. This user function decodes one MP3 frame and forwards the raw audio samples to the audio driver. As this is interrupt driven, the main function can still be used for other things.-dsp decompression IAR version I have written a simple program for the STM32F4 Discovery board that plays a short mp3 file　flash memory. For the decoding, the fixed point version of the Helix mp3 decoder is used. The audio output driver is the one used for the Peridiummmm demo, modified to use the peripheral library provided by ST. The audio driver has two DMA buffers and a callback function that asks a user-provided function to fill one buffer with audio data when it runs out, while the other DMA buffer is streamed to the audio CODEC. This user function decodes one MP3 frame and forwards the raw audio samples to the audio driver. As this is interrupt driven, the main function can still be used for other things.