s3tc-texsubimage: command not found

Maybe Your $PATH variable doesn't contain the default paths? echo $PATH should give something like:

[root@server ~]# echo $PATH
/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin

If it's empty, You may set the PATH variable with this command

export PATH="/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin"

On CentOS possible default full paths are:

/usr/lib64/piglit/bin/s3tc-texsubimage - from package: piglit

You may install the required package with command yum install {package}

Error in other languages:
s3tc-texsubimage: bevel nie gevind nie
s3tc-texsubimage: comandă negăsită
s3tc-texsubimage: comando não encontrado
s3tc-texsubimage: commande introuvable
s3tc-texsubimage: command not found
s3tc-texsubimage: käsku ei ole
s3tc-texsubimage: không tìm thấy lệnh
s3tc-texsubimage: komanda nerasta
s3tc-texsubimage: Kommando nicht gefunden.
s3tc-texsubimage: kommandot finns inte
s3tc-texsubimage: komut yok
s3tc-texsubimage: nie znaleziono polecenia
s3tc-texsubimage: níor aimsíodh an t-ordú
s3tc-texsubimage: no se encontró la orden
s3tc-texsubimage: no s'ha trobat l'ordre
s3tc-texsubimage: opdracht niet gevonden
s3tc-texsubimage: parancs nem található
s3tc-texsubimage: perintah tidak ditemukan
s3tc-texsubimage: príkaz nenájdený
s3tc-texsubimage: příkaz nenalezen
s3tc-texsubimage: команда не найдена
s3tc-texsubimage: командата не е открита
s3tc-texsubimage: 命令找不到
s3tc-texsubimage: コマンドが見つかりません