Hi Cesar,
If you don't want to use frame-length file then application has to allocate a large input buffer
which can hold say 10 frames, and after every VIDDEC3_process, input data needs to be shifted up.

In this case, you need to make these changes in viddec3test.
1) Allocate a large input buffer say 4MB or 8MB and set numBytes = size of valid bytes in the input buffer.
   validBytes = sizeof(inputbuffer);
    fread(decoder->input,  validBytes,  1, decoder->inFile);

2) After VIDDEC3_process call, memmove outArgs->bytesConsumed bytes up in the buffer, so that second frame's data is now at first byte position of input buffer.
memmove(decoder->input,   decoder-input+outArgs->bytesConsumed,   validBytes - outArgs->bytesConsumed);

3) Keep a track of how many bytes are left in the input buffer so that you load the remaining bytes from the file to input buffer. 
  For this you can set a threshold. Example
  if(remaining bytes <= 10% of inputBufferSize) 
     fread remaining bytes from file.

Ramprasad