// Q15 version int16_t fir_q15(int16_t input);
// Define the FIR filter coefficients float coefficients[] = 0.25, 0.5, 0.25; digital media processing dsp algorithms using c pdf
Digital Signal Processing (DSP) is a subfield of electrical engineering and computer science that deals with the processing and analysis of digital signals. DSP algorithms are used to extract, modify, and analyze the information contained in digital signals. In the context of digital media processing, DSP algorithms are used to process and transform digital media, such as audio, video, and images. // Q15 version int16_t fir_q15(int16_t input); // Define
#include #include typedef struct float *buffer; float *coeffs; uint32_t filterTapLength; uint32_t bufferIndex; FIRFilter; void FIR_Init(FIRFilter *filter, float *coefficients, uint32_t taps) filter->coeffs = coefficients; filter->filterTapLength = taps; filter->buffer = (float *)calloc(taps, sizeof(float)); filter->bufferIndex = 0; float FIR_Process(FIRFilter *filter, float inputSample) // Store latest sample in the circular buffer filter->buffer[filter->bufferIndex] = inputSample; float outputSample = 0.0f; uint32_t index = filter->bufferIndex; // Perform Multiply-Accumulate (MAC) operations for (uint32_t i = 0; i < filter->filterTapLength; i++) outputSample += filter->coeffs[i] * filter->buffer[index]; // Wrap around circular buffer backwards if (index == 0) index = filter->filterTapLength - 1; else index--; // Advance buffer pointer for the next sample filter->bufferIndex++; if (filter->bufferIndex >= filter->filterTapLength) filter->bufferIndex = 0; return outputSample; void FIR_Free(FIRFilter *filter) free(filter->buffer); Use code with caution. Infinite Impulse Response (IIR) Filters #include #include typedef struct float *buffer
In digital media processing, selecting the correct data type balances precision and computational efficiency:
typedef struct uint8_t r, g, b; RGBPixel; typedef struct uint8_t y, u, v; YUVPixel; void RGB_to_YUV444(const RGBPixel *rgb, YUVPixel *yuv, int total_pixels) for (int i = 0; i < total_pixels; i++) float r = rgb[i].r; float g = rgb[i].g; float b = rgb[i].b; // ITU-R BT.601 conversion formulas yuv[i].y = (uint8_t)( 0.299f * r + 0.587f * g + 0.114f * b); yuv[i].u = (uint8_t)(-0.169f * r - 0.331f * g + 0.500f * b + 128); yuv[i].v = (uint8_t)( 0.500f * r - 0.419f * g - 0.081f * b + 128); Use code with caution. Fixed-Point vs. Floating-Point Math