EE Graduate Seminar

Time-Varying Amplitude Compression Processing to
Preserve and Enhance Spectral Contrast in Speech Signals

Dr. Janet C. Rutledge
Dean, UMBC Graduate School
Vice-Provost for Graduate Education
Affiliate Associate Professor of Electrical Engineering

11:30-12:45 Friday, 18 November 2011, ITE 231

Multichannel amplitude compression processing is used to reduce the level variations of speech to fit the reduced dynamic ranges of listeners with sensorineural hearing loss. This processing, however, can result in smearing of temporal information, artifacts due to spectral discontinuities at fixed channel edges, and spectral flattening due to reduced peak-to-valley ratios. Presented here is an implementation of a time-varying compression processing algorithm based on a sinusoidal speech model. The algorithm operates on a time-varying, stimulus-dependent basis to adjust to the speech variations and the listeners hearing profile. The algorithm provides fast-acting compression with minimal artifact, has time-varying frequency channels, is computationally inexpensive and preserves the important spectral peaks in speech.

This method has been extended to provide real-time enhancement of spectral peaks and valleys. This work is also related to processing audio signals that will be transmitted over amplitude-limited noisy channels or for listeners in a noisy environment.

Dr. Janet Rutledge is Dean of the Graduate School and Affiliate Associate Professor in the CSEE Department at UMBC. She received the BS in electrical engineering from Rensselaer Polytechnic Institute and the MS and Ph.D. in electrical engineering from Georgia Tech. Prior to coming to UMBC in 2001, she was a faculty member at Northwestern University, and program director at the National Science Foundation.

Host: Prof. Joel M. Morris

Have old study habits let you down?  Get back on track by forming a study group! 

 - Stop by to get assistance with identifying study group members for your STEM Courses!!!

         • Targeting but not limited to:

                  -  Chem 101

                  -  Biol 141, 142

-       Math 106, 151, 152, 155

- Pick up your study group toolkit

- Register your study group by December 1^st to be entered into a drawing for FREE PIZZA!

Stop during any of my office hours:

Wednesday, November 16^th:  7-7:45pm, Patapsco Hall Rec Room

Thursday, November 17^th:  3:30-4:45pm, Chesapeake Hall Lobby

                                              5:00-6:15pm, Erickson Hall Lobby

Friday, November 18^th:  10:30am-11:45am, Patapsco Hall Lobby

                                         12:00-1:15pm, Main Street – Commons

                                         1:30-2:45pm, Susquehanna Hall Lobby

                                         3:00-4:15pm, Harbor Hall Lobby

Monday, November 21^st:  10:30 am-11:45am, Patapsco Hall Lobby

                                         12:00-1:15pm, Main Street – Commons

                                         1:30-2:45pm, Susquehanna Hall Lobby

                                         3:00-4:15pm, Harbor Hall Lobby

If you are unable to come to any of the events, you can also stop by my office to meet me and pick up your study group toolkits.  To schedule a 20 minute appointment, follow the link:  https://www.google.com/calendar/selfsched?sstoken=UURaS0VBMDN4VklsfGRlZmF1bHR8MWVlM2Q3ODkyODk1NzZmMWQ2NzFmYzdiZGRkMDU4Nzg.  

Genesis 16:1-16 (NIV)

Hagar and Ishmael

1 Now Sarai, Abram’s wife, had borne him no children. But she had an Egyptian slave named Hagar; 2 so she said to Abram, “The LORD has kept me from having children. Go, sleep with my slave; perhaps I can build a family through her.”

Abram agreed to what Sarai said. 3 So after Abram had been living in Canaan ten years, Sarai his wife took her Egyptian slave Hagar and gave her to her husband to be his wife. 4 He slept with Hagar, and she conceived.

When she knew she was pregnant, she began to despise her mistress. 5 Then Sarai said to Abram, “You are responsible for the wrong I am suffering. I put my slave in your arms, and now that she knows she is pregnant, she despises me. May the LORD judge between you and me.”

6 “Your slave is in your hands,” Abram said. “Do with her whatever you think best.” Then Sarai mistreated Hagar; so she fled from her.

7 The angel of the LORD found Hagar near a spring in the desert; it was the spring that is beside the road to Shur. 8 And he said, “Hagar, slave of Sarai, where have you come from, and where are you going?”

“I’m running away from my mistress Sarai,” she answered.

9 Then the angel of the LORD told her, “Go back to your mistress and submit to her.” 10 The angel added, “I will increase your descendants so much that they will be too numerous to count.”

11 The angel of the LORD also said to her:

“You are now pregnant

and you will give birth to a son.

You shall name him Ishmael,

for the LORD has heard of your misery.

12 He will be a wild donkey of a man;

his hand will be against everyone

and everyone’s hand against him,

and he will live in hostility

toward all his brothers.”

13 She gave this name to the LORD who spoke to her: “You are the God who sees me,” for she said, “I have now seen the One who sees me.” 14 That is why the well was called Beer Lahai Roi; it is still there, between Kadesh and Bered.

15 So Hagar bore Abram a son, and Abram gave the name Ishmael to the son she had borne.
16 Abram was eighty-six years old when Hagar bore him Ishmael.

Reflection:

Familiar to us is the story of how Abraham and Sarah bore their son Isaac in their old age. Perhaps not so familiar is the scandal, if you will, of Abraham and Hagar (the Egyptian slave), and the birth of their son, Ishmael. To no fault of her own, Hagar was put in a difficult situation by Sarai herself, the very one who is now mistreating her and causing her to run away. We find Hagar near a spring in the desert, confronted by an angel of the Lord. Reminiscent of Luke 7, Hagar comes to the realization of God’s character - that He is the God who sees. Just as Jesus saw the widow and her despair (Luke 7:13), God saw Hagar and her misery.

Responding to the Transmission:

God sees us and He has compassion on us when we suffer. Whatever circumstance or season we find ourselves in our walk of faith, may we come to the same realization that the widow and Hagar came to know, that our lives are seen by God. Let us seek the Lord today and pray for even more of His presence to guide us in our lives, in our ministries, in our churches.

Thanks to Politico!

How about a little geography? First, some history.

It seems as though ever since the passage of the unpopular No Child Left Behind Act in 2002, American children have been begging their politicians to leave the law behind.

In September, the Obama administration announced that states would be allowed to waive the applicability of certain aspects of NCLB if satisfactory conditions could be met.

So, a quiz: Which of the following 15 states have NOT taken advantage of the change and filed for a “No More” Waiver.

Colorado, Florida, Georgia, Arkansas,Indiana, Kentucky, Maryland, Massachusetts, Minnesota, New Jersey, New Mexico, Arizona, Rhode Island , Oklahoma, Tennessee

Hint: 11 States have filed for waivers.

The answer: Arkansas, Arizona, Maryland, Rhode Island

The real long term answer: change the law!