Video coding apparatus and video decoding apparatus

A video decoding apparatus comprising:

• an image decoding apparatus configured to decode coded data to generate a decoded image;
• and
• a resolution inverse conversion apparatus configured to convert a resolution of the decoded image to a specified resolution by using inverse conversion information, the resolution inverse conversion apparatus using a neural network, wherein
• information indicating a maximum value of a network parameter of the neural network in the resolution inverse conversion apparatus is decoded, and
• in deriving the maximum value of the network parameter, the maximum value is derived so as to not overflow in 64-bit integer arithmetic.

A video coding apparatus comprising:

• an image coding apparatus configured to code an image to generate coded data;
• an inverse conversion information generation apparatus configured to generate inverse conversion information for inversely converting a resolution of a decoded image in a case that the coded data is decoded;
• and
• an inverse conversion information coding apparatus configured to code the inverse conversion information as supplemental enhancement information, wherein
• in the inverse conversion information coding apparatus, information indicating the number of horizontal pixels and the number of vertical pixels of a patch size being a unit of processing of a neural network is coded, and
• the number of horizontal pixels and the number of vertical pixels of a coded image are set equal to a maximum value of the number of horizontal pixels and a maximum value of the number of vertical pixels of the patch size, respectively.

A video coding apparatus comprising:

• an image coding apparatus configured to code an image to generate coded data;
• an inverse conversion information generation apparatus configured to generate inverse conversion information for inversely converting a resolution of a decoded image in a case that the coded data is decoded;
• and
• an inverse conversion information coding apparatus configured to code the inverse conversion information as supplemental enhancement information, wherein
• information indicating a maximum value of a network parameter of a neural network in the inverse conversion information coding apparatus is coded, and
• in deriving the maximum value of the network parameter, the maximum value is derived so as to not overflow in 64-bit integer arithmetic.