Stafford Sven Tudor-Miles scanned photographs of adult porn stars into his computer and used sophisticated digital equipment to reduce the size of their breasts.

The images, which Tudor-Miles also manipulated with graphics software so that the women were partially dressed in school uniforms, appeared to be of girls aged under 18.

The 38-year-old fine art student was charged with possessing indecent pseudo-images of children. His barrister argued that the pictures were of adults and, therefore, no offence had been committed.

At an earlier court hearing, a judge had cast doubt on whether Tudor-Miles was guilty of any offence and used the analogy of a “tarts and vicars” party, suggesting that a photograph of women dressed as schoolgirls at such an event could not be considered child pornography.

David Lamb, for the defence, said that Tudor-Miles admitted doctoring the photographs but at no stage did the image become that of a child because the face remained the same.

Tudor-Miles entered guilty pleas at Teesside Crown Court yesterday after he failed in a final attempt to have the charges dismissed.

Judge Peter Fox released him on conditional bail but said that he should “be prepared, at least, for a prison sentence”.

The court was told that under the Protection of Children Act 1978, as amended by the Criminal Justice and Public Order Act 1994, a pseudophotograph of a child is defined as an image, whether made by computer graphics or otherwise, which appears to be that of a child.

Such an image is treated in law as showing a child even if some of the physical characteristics are those of an adult.

Tudor-Miles pleaded guilty to five counts of attempting to make indecent pseudo-photographs of children, one charge of possessing indecent pseudo-photographs and one of breaching a sex offenders’ order.

All the offences were committed in January and February and came to light after Tudor-Miles’s home in Easton, Middlesbrough, was raided by police.

The court was told that Tudor-Miles had asked his GP for help to reduce his urges and had also sought psychiatric help. He will be sentenced on September 8 after reports have been prepared.

Speaking after the hearing, Ray Savage, a forensic computer analyst for Cleveland Police, said it was unusual for a child porn case to feature doctored images.

“I’ve seen it in only two previous cases,” he said. “To create an image of a child by altering an image of an adult is just as serious as downloading child porn, and probably more worrying in terms of the time taken and work involved to produce such images.

“In general terms, these images can be as crude as someone having pasted a cut-out of a child’s head on to an adult’s photo.

“At the other end of the scale, someone will use sophisticated computer image manipulation equipment to alter the size of the breasts and genitalia to make a very realistic image.”

Four years ago, a lorry driver from Rutland admitted eight specimen charges at Leicester Crown Court of making an indecent pseudo-photograph of a child.

The amateur photographer, who was fined £100 for each offence, had taken snapshots of local children — some taken at village functions — before superimposing their faces on to the bodies of adults in explicit poses and storing the images on his computer.

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