generic-library/webp
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

gif2webp: Add '-min-size' option to get best compression.

Browse Source 
This disables key-frame insertion and tries both dispose methods for
each frame.

Change-Id: Ib167747198fd1d98cb93321f76826e91228f24d8
This commit is contained in:
Urvang Joshi
2014-10-30 15:17:09 -07:00
parent 77bdddf016
commit 7489b0e72b
4 changed files with 30 additions and 4 deletions
Download Patch File Download Diff File Expand all files Collapse all files

15
examples/gif2webp_util.c
View File

@@ -287,6 +287,9 @@ struct WebPFrameCache {
// transparent pixels in a frame.
int keyframe; // Index of selected keyframe relative to 'start'.
// TODO(urvang): Create a struct WebPAnimationEncodingConfig for these
// encoding parameters.
int min_size; // If true, produce the smallest output.
size_t kmin; // Min distance between key frames.
size_t kmax; // Max distance between key frames.
size_t count_since_key_frame; // Frames seen since the last key frame.
@@ -319,7 +322,7 @@ static void CacheReset(WebPFrameCache* const cache) {
cache->keyframe = KEYFRAME_NONE;
}
WebPFrameCache* WebPFrameCacheNew(int width, int height,
WebPFrameCache* WebPFrameCacheNew(int width, int height, int minimize_size,
size_t kmin, size_t kmax, int allow_mixed) {
WebPFrameCache* cache = (WebPFrameCache*)WebPSafeCalloc(1, sizeof(*cache));
if (cache == NULL) return NULL;
@@ -354,7 +357,12 @@ WebPFrameCache* WebPFrameCacheNew(int width, int height,
WebPUtilClearPic(&cache->prev_to_prev_canvas_disposed, NULL);
// Cache data.
cache->min_size = minimize_size;
cache->allow_mixed = allow_mixed;
if (cache->min_size) { // Disable keyframe insertion.
kmax = ~0;
kmin = kmax - 1;
}
cache->kmin = kmin;
cache->kmax = kmax;
cache->count_since_key_frame = 0;
@@ -790,7 +798,10 @@ static WebPEncodingError SetFrame(WebPFrameCache* const cache,
GetSubRect(prev_canvas_disposed, curr_canvas, orig_rect, is_key_frame,
&rect_bg, &sub_frame_bg);
if (RectArea(&rect_bg) < RectArea(&rect_none)) {
if (cache->min_size) { // Try both dispose methods.
try_dispose_bg = 1;
try_dispose_none = 1;
} else if (RectArea(&rect_bg) < RectArea(&rect_none)) {
try_dispose_bg = 1; // Pick DISPOSE_BACKGROUND.
try_dispose_none = 0;
}