Convert: cannot open image

[anju]

when i tried to merge lots of PDF/JPG/TTIF files into single PDF files, CONVERT command throws a error like saying file in the location cannot open

"convert: unable to open image `/var/www/': @ error/blob.c/OpenBlob/2517.
convert: unable to open image `/var/www/html/ib/mergeinv/medjavrgb*.jpg': @ error/blob.c/OpenBlob/2517.
convert: missing an image filename `/var/www/html/ib/mergeinv/javrgb08062012032553.pdf' @ error/convert.c/ConvertImageCommand/2953."

currently i am using command as below. First of all, i convered all the input files PDF, JPEG, TTIF into JPEG files and then merged all the JPEG files into single PDF.
v-command = 'convert -density 150 -strip -compress JPEG -quality 70' + ' ' + v-filelist ( input files) + ' -page A4 ' + v-opimage( output files).

v-command = 'convert -page A4 -strip -compress JPEG -quality 70'+ ' ' + v-finalpdf( output file) + ' ' + v-opfile ( input files) .

But when i tried to merge few files less than 40 files, CONVERT command merges files without any error.

Could anyone help please?

Thank you,
Anju

[fmw42]

But when i tried to merge few files less than 40 files, CONVERT command merges files without any error.

You may be running out of memory after some large number of files.