ocioconvert: 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/bin/ocioconvert - from package: OpenColorIO-tools

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

On Debian possible default full paths are:

/usr/bin/ocioconvert - from package: OpenColorIO-tools

You may install the required package with command apt-get install {package}

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