pagespeed::image_compression::WebpConfiguration Struct Reference

Inheritance diagram for pagespeed::image_compression::WebpConfiguration:

Public Types
typedef bool(*	WebpProgressHook )(int percent, void *user_data)

Public Member Functions
void	CopyTo (WebPConfig *webp_config) const

Public Attributes
int	lossless
	Lossless encoding (0=lossy(default), 1=lossless).
float	quality
	between 0 (smallest file) and 100 (biggest)
int	method
	quality/speed trade-off (0=fast, 6=slower-better)
int	target_size
	Parameters related to lossy compression only: More...
int	alpha_compression
	Takes precedence over the 'compression' parameter. More...
int	alpha_filtering
	1 = compressed with WebP lossless). Default is 1. More...
int	alpha_quality
	0: none, 1: fast, 2: best. Default is 1. More...
size_px	kmin
	Default is 100. More...
size_px	kmax
	Maximum keyframe interval. More...
WebpProgressHook	progress_hook
	If non-NULL, called during encoding.
void *	user_data

Member Typedef Documentation

typedef bool(* pagespeed::image_compression::WebpConfiguration::WebpProgressHook)(int percent, void *user_data)

This contains a subset of the options in WebPConfig and WebPPicture.

Member Data Documentation

int pagespeed::image_compression::WebpConfiguration::alpha_compression

Takes precedence over the 'compression' parameter.

Algorithm for encoding the alpha plane (0 = none,

int pagespeed::image_compression::WebpConfiguration::alpha_filtering

1 = compressed with WebP lossless). Default is 1.

Predictive filtering method for alpha plane.

int pagespeed::image_compression::WebpConfiguration::alpha_quality

0: none, 1: fast, 2: best. Default is 1.

Between 0 (smallest size) and 100 (lossless).

size_px pagespeed::image_compression::WebpConfiguration::kmax

Maximum keyframe interval.

non-keyframes between consecutive keyframes. If kmin == 0, keyframes are not used. Libwebp requires kmax > kmin >= (kmax / 2) + 1. Reasonable choices are (3,5) for lossy encoding and (9,17) for lossless encoding.

size_px pagespeed::image_compression::WebpConfiguration::kmin

Default is 100.

Parameters related to animated WebP: Minimum keyframe interval, i.e., number of

int pagespeed::image_compression::WebpConfiguration::target_size

Parameters related to lossy compression only:

if non-zero, set the desired target size in bytes.

void* pagespeed::image_compression::WebpConfiguration::user_data

Can be used by progress_hook. This

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The documentation for this struct was generated from the following file:

• pagespeed/kernel/image/webp_optimizer.h