How to fix low-volume audio/video files with FFMPEG (for normalization) and/or Audacity (for Dynamic Range Compression)

Because my Internet connection is very cranky, I download online videos and play them offline on my WDTV media player. The WDTV remote does not have volume control. After I installed the wdlxtv open-source firmware, it has lost function of the Mute button. Now, there is no way to increase or decrease the volume without getting up from the chair.

Different videos have different volume levels. I wrote a Nautilus Action Configuration and a bash script to normalize audio and video files before I copied them to WDTV. This worked fine for most files. Some video files continued to have low volume even though they were already normalized and couldn’t be normalized further. I then learned that this required the use of something called Dynamic Range Compression (DRC). DRC tries retains the waveform structure of the audio stream but compresses them against a threshold. Unfortunately, I compiled my FFMPEG binaries in 2013 and it did not seem to have filters for DRC.

In Audacity, I choose the Dynamic Range Compressor. You load an audio file, select Compression from the Effects menu, adjust the settings and click OK to compress the audio and export it to a new MP3 file. This couldn’t be automated.

I then used FFMPEG to replace the low-noise audio stream in the video with the compressed audio file generated by Audacity. In the FFMPEG command, I used to -i operators for two input files – the original video file and the new compressed audio file. I used the -map operator to copy the first stream of the first input file and the 3rd stream from the second input file to create a new video file. The second stream containing low-volume audio is dropped.

Thanks:

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Bike trip to Pothundi dam, Kesavanpara and Seetharkund at Nelliampathy Hills

There are many tourist places in Palakkkad and this holiday season I decided to cover most of them. Last Sunday, I went to Nelliampathy Hills. On the itinerary were Pothundi Dam, Kesavan Para and Seetharkundu.

Kesavan Para is a rock ledge in the middle of the Nelliampathy Hills. It provides a beautiful view overlooking the Pothundi Dam. Good for a picnic in a cooler or rainy season. Seetharkundu Viewpoint is a minor clearing in the wooded area overlooking the plains below. Seetharkundu is mainly known for tourist cottages and tea/fruit/vegetable plantations. Seetharkundu waterfalls cannot be reached from the Nelliampathy hills. The plains below in the foothills provide the entry for it.

First stop was Pothundi Dam. It is not as big as Malampuzha Dam but it is big all right. It is the height of summer now and there was not much water in the dam. On the other side of the water is a row of small hills – the Nelliampathy Hills. The dam was deserted at the top and most families took shelter in the park below. After a while, I decided to leave the dam for the tourist spots in the hills.

Pothundi Dam would be a good spot to visit during rainy season.

After taking this photo, the mobile phone ran out of charge. I brought my monster 20,000 mAH power bank with me and I put the phone under charge. So no photos or videos of the ascent. The road uphill reminded of Need for Speed games. In one place, you can see two small streams coming off a huge wall of rock. My guess is that during rainy season, these streams transform into reasonable waterfalls. In one NFS game, I have seen something similar. The road ended at a factory of AVT, the tea company. There the road forks into two. On the left, tea plantations and on the right, a footpath to Kesavan Para. I parked my bike and went up the path on foot. The footpath is covered on all sides by dense vegetation and was dark even at noon. A loud din of insects came from all sides. After a while the path cleared up and a large rock-covered area came. This is Kesavan Para. On the other side of the rock formation, there is ledge on the hillside where you can sit and view the Pothundi Dam. The hills you saw from the dam would now be flanking your sides. They rise for another hundred feet and you will be smack in the middle of it. I guess it must be magnificent during rainy season. Unfortunately, I have no photos of this place.

After lunch at a hotel, I left for Seetharkundu Viewpoint. This place is overrated, at least for one-dayers. If you plan on staying at one of the tourist cottages there, then it may be worthwhile. Because of the vegetation and the altitude, the place is much cooler than the plains down below. The place marked Seetharkund Viewpoint is a gap in the hillside where you can see the plains down below. I left after a few minutes. A tree struck by lightning in the area was more interesting. The phone was charged now and I was able to take photos and decided to record my descent.

This place reminded me of a level in Crysis 1, where you first attack a Korean military camp proper.

En route to Seetharkund, there are several tours arranged in tea plantations/factories and the vegetable/fruit farms but I did not take these tours. I was however surprised to know that there are tea plantations even in Palakkad.

A tea garden in Palakkad? Wow!

The descent was great and I could coast almost all the way down. On the way up, I saw some guys racing. One guy in a big bike gave the middle finger to a bullet and overtook him on a curve. I wouldn’t advise that to anyone. The ride downhill was fast but was still confusing. The tea farms have boards all over the place but proper road signs don’t exist. It was easy to go the wrong route. You can follow tourist vehicles but they can be very slow. On the way up, I saw a group of bikers thundering up a fork and then sheepishly turn around. So, it is better to rely on your own wits.

This must be the most boring unwatchable video in the world.

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Thiruvalathur Sree Rendumoorthy Bhagavathy Temple, Palakkad

Rendumoorthy means two gods or two faces. Interestingly there are two Rendumoorthy temples in Palakkad. There is one in Thiruvalathur. The other one is in Ottapalam and is dedicated to Lord Shiva and Lord Vishnu. Last week, I went to the Thiruvalathur temple.

The Thiruvalathur Sree Rendumoorthy Bhagavathy Kshetram is dedicated two godesses – Sree Mahishasuramardhini and Sree Annapoorneswari. The temple is quite old and was supposed to be built by devas in one night but they left it unfinished as they didn’t want to be seen by humans. The temple is open on all days with services in the morning and evening. I went in the evening hoping to see if the 4000 stone lamps around the temple are lit daily. A large group of ladies were chanting slokas near the diety of Sree Annapoorneswari but the lamps in the outer wall were not all lit. Hence, I will make a trip in the festival season November-December for that.

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Bike Trip to Palani – 2

Last month, I went to Pazhani again. This time, I took a bypass to the hill and saw a government-run parking lot. (You miss it when you come via town centre.)

Unlike the previous time, I decided not to climb the hill on empty stomach. I left home early morning after a coffee and no breakfast. So, first thing I did upon reaching the Pazhani was to have breakfast. This I hoped would enable me climb the hill without taking breaks. No such luck. I took two breaks. Where was I going wrong? I had been to Pazhani two or three times before by car and I did not have to take breaks. Maybe that was it – car. My legs were tired riding the bike. I couldn’t believe legs could get tired by riding a bike. Apparently, this can happen. On the way back, I wanted to go to an ATM and I found that I couldn’t take easy steps. Maybe, next time, I will take a car and see if I am any good.

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No more world peace as FARC rebels call the bluff on beauty pageants!

What can bikini-clad beauty pageant contestants do to bring world peace?

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EmailTweetor v2018.03.04 for Android adds icon to delete tweets by URL

http://vsubhash.com/article.asp?id=133&info=EmailTweetor_app_for_Android

The fire extinguisher icon does it. The text of the deleted message will be echoed on the screen on last time. It will also be copied to the email for whatever reason you might need it.

https://twitter.com/SubhashBrowser/status/978959332522868736

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The Russian Samovar from the Leo Tolstoy story in CBSE/NCERT English reader

https://www.youtube.com/watch?v=8leBaMJEvY8
It apparently has Persian & Kashmiri variants – all known by the same name.

https://en.wikisource.org/wiki/Best_Russian_Short_Stories/God_Sees_the_Truth,_but_Waits

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