Method (ImgDec) for decoding-decompressing a compressed-encoded digital data sequence (Bitstream) relating to at least an initial compressed-encoded digital image (Imgn) and for providing at least a respective decoded-decompressed digital image (Îmgn), the method comprising the steps of: - receiving (Rx_Parse) said digital data sequence (BitStream) comprising compressed-encoded data groups separated from one another by at least one restart marker and each one including a respective plurality of encoded data structures, said receiving step including the operation of detecting (RM_Detect) in said received sequence a first restart marker (RM1n) and a second restart marker (RM2n) subsequent to the first restart marker (RMln), said detected markers signaling, respectively, the start of a first data group (VPln) to be decoded in the sequence received and the start of a second data group (VP2n); - a first reading operation for reading a first piece of information representative of the position within the image (Imgn) of the first encoded data structure comprised in said first data group, said first piece of information being read from a first heading comprised/associated in/to said first data group; and - a second reading operation for reading a second piece of information representative of the position, within the image Imgn, of the first encoded data structure comprised in said second data group, said second piece of information being read from a second heading comprised/associated in/to said second data group; - calculating (RM_Detect), after said detecting operation, a representative value of the number of encoded data structures comprised between said first restart marker (RM1n) and said second restart marker, said representative value being calculated on the basis of one said first and said second piece of information, - extracting (MB_Extract), after said detecting operation of both said first and second restart markers and after said calculating step, from said first data group to be decoded the encoded data structures comprised therein and counting the number of extracted data structures, wherein said counting includes, parallel to said extracting (MB_Extract), keeping an updated count number representative of the number of data structures extracted (MB_Extract); - detecting (MB_Check) the presence of at least one error, if said counted number of extracted data structures is different from said calculated representative value; - a group concealment step (VP_Conceal) for discarding, if the presence of at least one error is detected, at least part of the data comprised between said first (RM1n) and said second (RM2n) restart marker, thus providing in the decoded-decompressed image replacement information; and - an entropic decoding step. - receiving (Rx_Parse) said digital data sequence (BitStream) comprising compressed-encoded data groups separated from one another by at least one restart marker and each one including a respective plurality of encoded data structures, said receiving step including the operation of detecting (RM_Detect) in said received sequence a first restart marker (RM1n) and a second restart marker (RM2n) subsequent to the first restart marker (RMln), said detected markers signaling, respectively, the start of a first data group (VPln) to be decoded in the sequence received and the start of a second data group (VP2n); - a first reading operation for reading a first piece of information representative of the position within the image (Imgn) of the first encoded data structure comprised in said first data group, said first piece of information being read from a first heading comprised/associated in/to said first data group; and - a second reading operation for reading a second piece of information representative of the position, within the image Imgn, of the first encoded data structure comprised in said second data group, said second piece of information being read from a second heading comprised/associated in/to said second data group; - calculating (RM_Detect), after said detecting operation, a representative value of the number of encoded data structures comprised between said first restart marker (RM1n) and said second restart marker, said representative value being calculated on the basis of one said first and said second piece of information, - extracting (MB_Extract), after said detecting operation of both said first and second restart markers and after said calculating step, from said first data group to be decoded the encoded data structures comprised therein and counting the number of extracted data structures, wherein said counting includes, parallel to said extracting (MB_Extract), keeping an updated count number representative of the number of data structures extracted (MB_Extract); - detecting (MB_Check) the presence of at least one error, if said counted number of extracted data structures is different from said calculated representative value; - a group concealment step (VP_Conceal) for discarding, if the presence of at least one error is detected, at least part of the data comprised between said first (RM1n) and said second (RM2n) restart marker, thus providing in the decoded-decompressed image replacement information; and - an entropic decoding step.