目录
Series Editors' Preface
Acknowledgements
CHAPTER ONE An overview of listening comprehension
CHAPTER TWO What is unique to listening
CHAPTER THREE Approaches to assessing listening
CHAPTER FOUR Defining the construct
CHAPTER FIVE Creating tasks
CHAPTER SIX Providing suitable texts
CHAPTER SEVEN Designing and constructing complete assessments
CHAPTER EIGHT Illustrative tests of listening comprehension
CHAPTER NINE Summary and future developments
Bibliography
Index
摘要
First load the recording into the computer. Sound files are huge: CD- quality stereo sound, music or voice (i.e. 16 bits, sampled 44,100 times a second, on two channels) occupies 10 megabytes of storage per minute of sound. For voice, 16 bits sampled 22,050 times a second on one mono channel is quite good enough, but this still requires 2.5 megabytes per minute of recording. Make sure you have sufficient storage space. You may want to buy a new hard disk if you are going to process a lot of audio. After loading the audio file into the audio- processing software, it will show you a waveform of the recorded sound. This waveform is what you work with. You can zoom in to look at the waveform for just one word, or zoom out to see the whole recording. You can copy and cut and paste the recording by manipulating the wave form.
First, listen to the whole recording and decide what you want to keep and what you want to delete. Usually, the first editing task is to determine the length. Find where the speaker starts and delete everything before then, perhaps leaving half a second of silence before the voice actually comes in. Do the same at the end.
Now look for any serious problems. If there are any unnaturally long pauses, or if the recording went wrong, or if there are any unwanted noises - a telephone ringing, people interrupting or the speaker saying something inappropriate - try to cut it out. You can delete it just like deleting a word in a word processor. If you want to delete something, but do not want to shorten the recording, you can replace it with silence. Just copy a piece of silence from anywhere on the tape, a pause where the speaker is silent, then replace the noise with it. It should sound very natural. Alternatively, you can just high-light the unwanted noise, and reduce the volume until it is very low.……
