Documentation ¶
Overview ¶
Package fastjpeg uses djpeg(1), from the Independent JPEG Group's (www.ijg.org) jpeg package, to quickly down-sample images on load. It can sample images by a factor of 1, 2, 4 or 8. This reduces the amount of data that must be decompressed into memory when the full resolution image isn't required, i.e. in the case of generating thumbnails.
Index ¶
Constants ¶
This section is empty.
Variables ¶
var (
ErrDjpegNotFound = errors.New("fastjpeg: djpeg not found in path")
)
Functions ¶
func DecodeDownsample ¶
DecodeDownsample decodes JPEG data in r, down-sampling it by factor. If djpeg is not found, err is ErrDjpegNotFound and r is not read from. If the execution of djpeg, or decoding the resulting PNM fails, error will be of type DjpegFailedError.
Types ¶
type DjpegFailedError ¶
type DjpegFailedError struct {
Err error
}
DjpegFailedError wraps errors returned when calling djpeg and handling its response. Used for type asserting and retrying with other jpeg decoders, i.e. the standard library's jpeg.Decode.
func (DjpegFailedError) Error ¶
func (dfe DjpegFailedError) Error() string