Help....

Hi every one
I am building a new page for my channel but I don't understand how to associate a picture to my streaming or video on demand...
follow the script: Thank you !!!

' *********************************************************
' ** Simple Poster Screen Demonstration App
' ** Nov 2009
' ** Copyright (c) 2009 Roku Inc. All Rights Reserved.
' *********************************************************

'************************************************************
'** Application startup
'************************************************************
Sub Main()

'initialize theme attributes like titles, logos and overhang color
initTheme()

'prepare the screen for display and get ready to begin
screen=preShowPosterScreen("", "")
if screen=invalid then
print "unexpected error in preShowPosterScreen"
return
end if

'set to go, time to get started
showPosterScreen(screen)

End Sub


'*************************************************************
'** Set the configurable theme attributes for the application
'**
'** Configure the custom overhang and Logo attributes
'** These attributes affect the branding of the application
'** and are artwork, colors and offsets specific to the app
'*************************************************************

Sub initTheme()

app = CreateObject("roAppManager")
theme = CreateObject("roAssociativeArray")

theme.OverhangOffsetSD_X = "72"
theme.OverhangOffsetSD_Y = "25"
theme.OverhangSliceSD = "pkg:/images/Overhang_BackgroundSlice_Blue_SD43.png"
theme.OverhangLogoSD = "pkg:/images/Logo_Overhang_Roku_SDK_SD43.png"

theme.OverhangOffsetHD_X = "123"
theme.OverhangOffsetHD_Y = "48"
theme.OverhangSliceHD = "pkg:/images/Overhang_BackgroundSlice_Blue_HD.png"
theme.OverhangLogoHD = "pkg:/images/Logo_Overhang_Roku_SDK_HD.png"

app.SetTheme(theme)

End Sub

'******************************************************
'** Perform any startup/initialization stuff prior to
'** initially showing the screen.
'******************************************************
Function preShowPosterScreen(breadA=invalid, breadB=invalid) As Object

port=CreateObject("roMessagePort")
screen = CreateObject("roPosterScreen")
screen.SetMessagePort(port)
if breadA<>invalid and breadB<>invalid then
screen.SetBreadcrumbText(breadA, breadB)
end if

screen.SetListStyle("arced-landscape")
return screen

End Function


'******************************************************
'** Display the poster screen and wait for events from
'** the screen. The screen will show retreiving while
'** we fetch and parse the feeds for the show posters
'******************************************************
Function showPosterScreen(screen As Object) As Integer

categoryList = getCategoryList()
screen.SetListNames(categoryList)
screen.SetContentList(getShowsForCategoryItem(categoryList[0]))
screen.Show()

while true
msg = wait(0, screen.GetMessagePort())
if type(msg) = "roPosterScreenEvent" then
print "showPosterScreen | msg = "; msg.GetMessage() " | index = "; msg.GetIndex()
if msg.isListFocused() then
'get the list of shows for the currently selected item
screen.SetContentList(getShowsForCategoryItem(categoryList[msg.GetIndex()]))
print "list focused | current category = "; msg.GetIndex()
else if msg.isListItemFocused() then
print"list item focused | current show = "; msg.GetIndex()
else if msg.isListItemSelected() then
print "list item selected | current show = "; msg.GetIndex()
'if you had a list of shows, the index of the current item
'is probably the right show, so you'd do something like this
'm.curShow = displayShowDetailScreen(showList[msg.GetIndex()])
displayBase64()
else if msg.isScreenClosed() then
return -1
end if
end If
end while


End Function

Function displayBase64()
ba = CreateObject("roByteArray")
str = "Aladdin:open sesame"
ba.FromAsciiString(str)
result = ba.ToBase64String()
print result

ba2 = CreateObject("roByteArray")
ba2.FromBase64String(result)
result2 = ba2.ToAsciiString()
print result2
End Function

'**********************************************************
'** When a poster on the home screen is selected, we call
'** this function passing an roAssociativeArray with the
'** ContentMetaData for the selected show. This data should
'** be sufficient for the springboard to display
'**********************************************************
Function displayShowDetailScreen(category as Object, showIndex as Integer) As Integer

'add code to create springboard, for now we do nothing
return 1

End Function


'**************************************************************
'** Return the list of categories to display in the filter
'** banner. The result is an roArray containing the names of
'** all of the categories. All just static data for the example.
'***************************************************************
Function getCategoryList() As Object

categoryList = CreateObject("roArray", 10, true)

categoryList = [ "Live Streaming & VOD"]
return categoryList

End Function


'********************************************************************
'** Given the category from the filter banner, return an array
'** of ContentMetaData objects (roAssociativeArray's) representing
'** the shows for the category. For this example, we just cheat and
'** create and return a static array with just the minimal items
'** set, but ideally, you'd go to a feed service, fetch and parse
'** this data dynamically, so content for each category is dynamic
'********************************************************************
Function getShowsForCategoryItem(category As Object) As Object

print "getting shows for category "; category

showList = [
{
ShortDescriptionLine1:"IRoad Italian Channel",
ShortDescriptionLine2:"Live Streaming",
HDPosterUrl:"pkg:/images/mm_icon_focus_hd.jpg",
SDPosterUrl:"pkg:/images/mm_icon_focus_sd.jpg"
}
{
ShortDescriptionLine1:"L'Italia del Futuro",
ShortDescriptionLine2:"VOD - 150 anniversario Unita' d'Italia",
HDPosterUrl:"http://www.iroadlive.com/images/media/italia.jpg",
SDPosterUrl:"http://www.iroadlive.com/images/media/italia.jpg"
}
{
ShortDescriptionLine1:"Coming Soon",
ShortDescriptionLine2:"VOD - Coming Soon",
HDPosterUrl:"http://www.iroadlive.com/images/media/comingsoon.jpg",
SDPosterUrl:"http://www.iroadlive.com/images/media/viale.jpg"
}
{
ShortDescriptionLine1:"Coming Soon",
ShortDescriptionLine2:"VOD - Coming Soon",
HDPosterUrl:"http://www.iroadlive.com/images/media/comingsoon.jpg",
SDPosterUrl:"http://www.iroadlive.com/images/media/eco.jpg"
}
{
ShortDescriptionLine1:"Coming Soon",
ShortDescriptionLine2:"VOD - Coming Soon",
HDPosterUrl:"http://www.iroadlive.com/images/media/comingsoon.jpg",
SDPosterUrl:"http://www.iroadlive.com/images/media/putman.jpg"
}
{
ShortDescriptionLine1:"Coming Soon",
ShortDescriptionLine2:"VOD - Coming Soon",
HDPosterUrl:"http://www.iroadlive.com/images/media/comingsoon.jpg",
SDPosterUrl:"http://www.iroadlive.com/images/media/molinari.jpg"
}
{
ShortDescriptionLine1:"Coming Soon",
ShortDescriptionLine2:"VOD - Coming Soon",
HDPosterUrl:"http://www.iroadlive.com/images/media/comingsoon.jpg",
SDPosterUrl:"http://www.iroadlive.com/images/media/comingsoon.jpg"
}
{
ShortDescriptionLine1:"Coming Soon",
ShortDescriptionLine2:"VOD - Coming Soon",
HDPosterUrl:"http://www.iroadlive.com/images/media/comingsoon.jpg",
SDPosterUrl:"http://www.iroadlive.com/images/media/comingsoon.jpg"
}
{
ShortDescriptionLine1:"Coming Soon",
ShortDescriptionLine2:"VOD - Coming Soon",
HDPosterUrl:"http://www.iroadlive.com/images/media/comingsoon.jpg",
SDPosterUrl:"http://www.iroadlive.com/images/media/comingsoon.jpg"
}
{
ShortDescriptionLine1:"Coming Soon",
ShortDescriptionLine2:"VOD - Coming Soon",
HDPosterUrl:"http://www.iroadlive.com/images/media/comingsoon.jpg",
SDPosterUrl:"http://www.iroadlive.com/images/media/comingsoon.jpg"
}
]

return showList

End Function