A Faster ESP32 JPEG Decoder? An intriguing issue appeared in the esp32-tv project that deals with speeding up JPEG file decoding using SIMD (Single Instruction Multiple Data) instructions, showing immense performance boost. However, there were some notable differences in speed when it comes to drawing the images versus simply decoding them. The problem was found to be with the DMA drawing mechanism and the way the new fast library decodes the image all at once. But despite this hiccup, by overlapped decoding and displaying process, a high frame rate can still be achieved. Joined me in this dissecting process and my initial tests showing approximately... 30 September 2023
ESP32 I2S DMA Settings - dma_buf_len and dma_buf_count Explained In this blog post, we delve deep into the intriguing concepts of I2S audio and DMA, particularly focusing on parameters like dma_buf_count and dma_buf_len. We explore their roles, ideal values, and the impacts they have on aspects such as CPU load and latency. We also discuss the limitations that come hand in hand with these parameters. This post aims to provide you some insights on trading-off between latency, CPU load, memory usage and the overall buffer space allocation. However, the primary takeaway remains that the optimal configurations largely depend on individual context and application needs. 20 April 2021
ESP32 Audio Input - MAX4466, MAX9814, SPH0645LM4H, INMP441 In this blog post, I've delved deep into the world of audio input for ESP32, exploring all the different options for getting analogue audio data into the device. After discussing the use of the built-in Analogue to Digital Converts (ADCs), I2S to read ADCs with DMA, and using I2S to read directly from compatible peripherals, I go on to present hands-on experiments with four different microphones (MAX4466, MAX9814, SPH0645, INPM441). This comprehensive look at getting audio into the ESP32 should be a valuable resource for anyone hungry for a deep-dive into ESP32's audio capabilities, complete with YouTube videos for an... 12 September 2020