In an embodiment, a first individual image and a second individual image constituting an encoded stereoscopic image, for example in JPEG format with respective levels of encoding quality and united in a multiple-image file, for example of the Multiple-Picture Object (MPO) type. The second level of encoding quality is lower than the first level of encoding quality. During decoding, the first individual image encoded with a first level of encoding quality and the second individual image encoded with a second level of encoding quality lower than the first level of encoding quality are extracted from the multiple-image file, then using information of the first extracted individual image for enhancing the second extracted individual image.