motion.c File Reference

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#include "motion.h"
#include <math.h>
#include <assert.h>
#include <string.h>
#include "esp_heap_caps.h"
#include "esp_log.h"

Functions
void	uninit (MotionEstContext *ctx)
bool	init_context (MotionEstContext *ctx)
	Init & allocate context ctx accordingly to the method used. More...
bool	motion_estimation (MotionEstContext *ctx, uint8_t *img_prev, uint8_t *img_cur)
	motion estimation wrapper More...
uint64_t	me_comp_sad (MotionEstContext *me_ctx, int x_mb, int y_mb, int x_mv, int y_mv)
	omputes the Sum of Absolute Difference (SAD) for the given two blocks More...

Detailed Description

motion header

Author

Thomas Pegot

Thomas Pegot

Function Documentation

init_context()

bool init_context

(

MotionEstContext *

ctx

)

Init & allocate context ctx accordingly to the method used.

Parameters

ctx	: motion estimation context object

Returns

big if true

me_comp_sad()

uint64_t me_comp_sad	(	MotionEstContext *	me_ctx,
		int	x_mb,
		int	y_mb,
		int	x_mv,
		int	y_mv
	)

omputes the Sum of Absolute Difference (SAD) for the given two blocks

\[ SAD = \sum_{i=0}^{mbSize}\sum_{j=0}^{mbSize} |Cur_{ij}-Ref_{ij}| \]

Used as cost function for EPZS algorithm.

Todo:

Change ARPS algo such as it uses this function instead of its own

Parameters

me_ctx
x_mb	curr frame x located MB (MacroBlock)
y_mb	curr frame y located MB
x_mv	prev frame x located MB
y_mv	prev frame y located MB

Returns

uint64_t

motion_estimation()

bool motion_estimation	(	MotionEstContext *	ctx,
		uint8_t *	img_prev,
		uint8_t *	img_cur
	)

motion estimation wrapper

• Will update ctx->name representation of the motion estimation algo used.
• Will call motion estimation algo accordingly (motionEstARPS, motionEstEPZS, LK...)
• current Motion Vector will be saved in mv_table[0].

Example usage :

MotionEstContext * motion(uint8_t *img_prev, uint8_t *img_cur, size_t w, size_t h)
{
    // Generate a motion context configuration 
    MotionEstContext me_ctx = {.method = LK_OPTICAL_FLOW,    // algorithm used
                               .width  = w,  .height = h // size of your image
                              };
    // Init the context 
    init_context(&me_ctx);
 
    // Start the motion estimation
    if(!motion_estimation(&me_ctx, (uint8_t *)img_prev, (uint8_t *)img_cur)) {
        // If motion fail return 0
        printf("error");
 
    return &me_ctx;
}

Note

Some algo will save previous motion into mv_table[1] and mv_table[2]

Parameters

ctx	Motion vectors will be saved in (MotionVector16_t) ctx->mv_table[0]

Returns

Big if True

uninit()

void uninit

(

MotionEstContext *

ctx

)