lattice-tool -ppl not working for me

[Michael Harville]

Hi,

Please excuse the newbie question, but I have searched the archives and web for an answer, and have not been able to find one. I am running the following command:

echo "HUGE WIN OVER RUTGERS" > sentence.txt
lattice-tool -ppl sentence.txt -in-lattice footballPodcast.lat -read-htk -debug 2 -order 4

and am getting the folllowing results:

        p( HUGE | <s> )         =  0 [ -inf ]
        p( WIN | HUGE ...)      =  0 [ -inf ]
        p( OVER | WIN ...)      =  0 [ -inf ]
        p( RUTGERS | OVER ...)  =  0 [ -inf ]
        p( </s> | RUTGERS ...)  =  0 [ -inf ]
Viterbi backtrace failed
1 sentences, 4 words, 0 OOVs
5 zeroprobs, logprob= 0 ppl= undefined ppl1= undefined

Anyone know what might be going on? The original utterance from which the lattice was built is 2 minutes long, containing much more speech than just the four word sentence I am testing on. Is that the problem?

Generally speaking, I am looking for a tool that can give me the highest probability location (along with the associated probability) of where a sequence of words was spoken in an audio file. I am using Sphinx 3.7 to generate lattices from the audio, and have been using various SRILM tools to examine these lattices. Is there a tool that does what I want, or will I need to make one?

Much thanks in advance!
Mike