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speed-up SSIM calculation

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SSIM results are incompatible with previous version!
We're now averaging the SSIM value for each pixels instead of
printing a frame-level global SSIM value.

* Got rid of some old code
* switched to uint32_t for accumulation
* refactoring

SSIM calculation is ~4x faster now.

Change-Id: I48d838e66aef5199b9b5cd5cddef6a98411f5673
This commit is contained in:
Pascal Massimino
2016-09-14 16:15:43 +02:00
parent 64577de8ae
commit bfff0bf329
5 changed files with 143 additions and 201 deletions
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29
src/dsp/dsp.h
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@ -254,26 +254,29 @@ void VP8EncDspCostInit(void);
// struct for accumulating statistical moments
typedef struct {
double w; // sum(w_i) : sum of weights
double xm, ym; // sum(w_i * x_i), sum(w_i * y_i)
double xxm, xym, yym; // sum(w_i * x_i * x_i), etc.
uint32_t w; // sum(w_i) : sum of weights
uint32_t xm, ym; // sum(w_i * x_i), sum(w_i * y_i)
uint32_t xxm, xym, yym; // sum(w_i * x_i * x_i), etc.
} VP8DistoStats;
// Compute the final SSIM value
// The non-clipped version assumes stats->w = (2 * VP8_SSIM_KERNEL + 1)^2.
double VP8SSIMFromStats(const VP8DistoStats* const stats);
double VP8SSIMFromStatsClipped(const VP8DistoStats* const stats);
#define VP8_SSIM_KERNEL 3 // total size of the kernel: 2 * VP8_SSIM_KERNEL + 1
typedef void (*VP8SSIMAccumulateClippedFunc)(const uint8_t* src1, int stride1,
const uint8_t* src2, int stride2,
int xo, int yo, // center position
int W, int H, // plane dimension
VP8DistoStats* const stats);
typedef double (*VP8SSIMGetClippedFunc)(const uint8_t* src1, int stride1,
const uint8_t* src2, int stride2,
int xo, int yo, // center position
int W, int H); // plane dimension
// This version is called with the guarantee that you can load 8 bytes and
// 8 rows at offset src1 and src2
typedef void (*VP8SSIMAccumulateFunc)(const uint8_t* src1, int stride1,
const uint8_t* src2, int stride2,
VP8DistoStats* const stats);
typedef double (*VP8SSIMGetFunc)(const uint8_t* src1, int stride1,
const uint8_t* src2, int stride2);
extern VP8SSIMAccumulateFunc VP8SSIMAccumulate; // unclipped / unchecked
extern VP8SSIMAccumulateClippedFunc VP8SSIMAccumulateClipped; // with clipping
extern VP8SSIMGetFunc VP8SSIMGet; // unclipped / unchecked
extern VP8SSIMGetClippedFunc VP8SSIMGetClipped; // with clipping
typedef uint32_t (*VP8AccumulateSSEFunc)(const uint8_t* src1,
const uint8_t* src2, int len);