mirror of
https://github.com/webmproject/libwebp.git
synced 2024-12-27 06:08:21 +01:00
e8ab6a825a
This function returns a rough estimation of the quality factor used for compressing the WebP bitstream. Simple command line: 'webp_quality [-quiet] in.webp' should print the estimated quality factor. Change-Id: Ifba3e489461f5a587003ac9f08cc7556e9b24ac2
50 lines
1.4 KiB
C
50 lines
1.4 KiB
C
// Simple tool to roughly evaluate the quality encoding of a webp bitstream
|
|
//
|
|
// Result is a *rough* estimation of the quality. You should just consider
|
|
// the bucket it's in (q > 80? > 50? > 20?) and not take it for face value.
|
|
/*
|
|
gcc -o webp_quality webp_quality.c -O3 -I../ -L. -L../imageio \
|
|
-lexample_util -limagedec -lwebpextras -lwebp -L/opt/local/lib \
|
|
-lpng -lz -ljpeg -ltiff -lm -lpthread
|
|
*/
|
|
|
|
#include <stdio.h>
|
|
#include <stdlib.h>
|
|
#include <string.h>
|
|
|
|
#include "./extras.h"
|
|
#include "../imageio/example_util.h"
|
|
|
|
int main(int argc, const char *argv[]) {
|
|
int c;
|
|
int quiet = 0;
|
|
for (c = 1; c < argc; ++c) {
|
|
if (!strcmp(argv[c], "-quiet")) {
|
|
quiet = 1;
|
|
} else if (!strcmp(argv[c], "-help") || !strcmp(argv[c], "-h")) {
|
|
printf("webp_quality [-h][-quiet] webp_files...\n");
|
|
return 1;
|
|
} else {
|
|
const char* const filename = argv[c];
|
|
const uint8_t* data = NULL;
|
|
size_t data_size = 0;
|
|
int q;
|
|
const int ok = ExUtilReadFile(filename, &data, &data_size);
|
|
if (!ok) continue;
|
|
q = VP8EstimateQuality(data, data_size);
|
|
if (!quiet) printf("[%s] ", filename);
|
|
if (q < 0) {
|
|
fprintf(stderr, "Not a WebP file, or not a lossy WebP file.\n");
|
|
} else {
|
|
if (!quiet) {
|
|
printf("Estimated quality factor: %d\n", q);
|
|
} else {
|
|
printf("%d\n", q); // just print the number
|
|
}
|
|
}
|
|
free((void*)data);
|
|
}
|
|
}
|
|
return 1;
|
|
}
|