Image processing apparatus, image processing method and storage medium

A method of synthesizing a first image including a transparency-process region and a non-transparency region, and a second image, the method comprising:

• storing, in a memory, a first color value as transparency-process color information useable for performing a transparency-process to the transparency-process region of the first image;
• extracting, from the first image, the non-transparency region and a part of the transparency-process region that are adjacent with each other as a process target region;
• comparing a color value of the non-transparency region and the first color value of the transparency-process region that are adjacent with each other and existing in the process target region;
• changing the transparency-process color information from the first color value to a second color value depending on a comparison result of the color value of the non-transparency region and the first color value of the transparency-process region, the second color value being set closer to the color value of the non-transparency region;
• applying the second color value to the transparency-process region existing in the process target region;
• enlarging an image size of the process target region having the transparency-process region applied with the second color value in view of an image size of the second image;
• performing the transparency process to the enlarged process target region based on the second color value;
• and
• superimposing the enlarged process target region having received the transparency process on the second image to output as a superimposed image.

A non-transitory storage medium storing a program that, when executed by a computer, causes the computer to execute a method of synthesizing a first image including a transparency-process region and a non-transparency region, and a second image, the method comprising:

• storing, in a memory, a first color value as transparency-process color information useable for performing a transparency-process to the transparency-process region of the first image;
• extracting, from the first image, the non-transparency region and a part of the transparency-process region that are adjacent with each other as a process target region;
• comparing a color value of the non-transparency region and the first color value of the transparency-process region that are adjacent with each other and existing in the process target region;
• changing the transparency-process color information from the first color value to a second color value depending on a comparison result of the color value of the non-transparency region and the first color value of the transparency-process region, the second color value being set closer to the color value of the non-transparency region;
• applying the second color value to the transparency-process region existing in the process target region;
• enlarging an image size of the process target region having the transparency-process region applied with the second color value in view of an image size of the second image;
• performing the transparency process to the enlarged process target region based on the second color value;
• and
• superimposing the enlarged process target region having received the transparency process on the second image to output as a superimposed image.