Inverted Video

Started by Anonymous in comp.dsp12 years ago 15 replies

"Simon S Aysdie" wrote > Why is video inverted for transmission? So that the peaks of sync pulses are transmitted at +100%...

"Simon S Aysdie" wrote > Why is video inverted for transmission? So that the peaks of sync pulses are transmitted at +100% modulation, which allows TV receivers to show the most stable picture in the presence of noise (eg, fringes of the coverage area of the TV station). RF RCA Broadcast Field Engineer, retired


Video: DC Motor Basics

Started by Tim Wescott in comp.dsp2 years ago 7 replies

Normally it takes me a while to get a video out. This one came to me and practically pushed it's way out of my brain and into the camera. I...

Normally it takes me a while to get a video out. This one came to me and practically pushed it's way out of my brain and into the camera. I hope y'all like it: https://www.youtube.com/watch?v=E9zM07v1vWk -- Tim Wescott Control systems, embedded software and circuit design I'm looking for work! See my website if you're interested http://www.wescottdesign.com


Using to QAM to compress video/audio -- practical or not?

Started by Green Xenon [Radium] in comp.dsp12 years ago 6 replies

Hi: Is it rational to compress video/audio -- for storing in a device with limited capacity or transferring on the internet via low-bandwidth...

Hi: Is it rational to compress video/audio -- for storing in a device with limited capacity or transferring on the internet via low-bandwidth connection -- using QAM? Has this ever been done before? If so, what did the resulting artifacts look/sound like? Thanks, Radium


video format .bix .box

Started by SpringTime in comp.dsp13 years ago

There is video format with file extension .bix .box . It was mainly used for surveillance systems. Does anyone know about its compression,...

There is video format with file extension .bix .box . It was mainly used for surveillance systems. Does anyone know about its compression, player/viewer and about enhancing it? Thanks, ST


How to do Chroma Decimation

Started by Anonymous in comp.dsp13 years ago 3 replies

Hi, I am a university student working on a real-time video conferencing project. I'm trying to find a compression solution that will be...

Hi, I am a university student working on a real-time video conferencing project. I'm trying to find a compression solution that will be quick enough to give me the throughput I need, but will also give me the compression ratio I need. Each of my video frames are 320x240 pixels and each pixel has 3 bytes associated with it (R,G,B). For further information, see a post that I made to comp....


using MCBSP and MCASP

Started by devi in comp.dsp13 years ago

hi, I'm trying to interface audio codec and SDcard with DSP[DM642]... SDcard is connected with MCBSP port and audio codec is connected...

hi, I'm trying to interface audio codec and SDcard with DSP[DM642]... SDcard is connected with MCBSP port and audio codec is connected with MCASP0.... I'm also using Video port 1 and video port 2.. In the datasheet, it is given that MCASP0's control is in videoport 0 and data is in videoport 1... My doubt is i'm using videoport 1 for video in interfacing... If i connect the MCASP...


MPEG mistake

Started by glen herrmannsfeldt in comp.dsp8 years ago 3 replies

While posting to the DCT vs. FFT discussion, I was reminded of some thoughts related to MPEG and video compression. It seems to me that one...

While posting to the DCT vs. FFT discussion, I was reminded of some thoughts related to MPEG and video compression. It seems to me that one case that MPEG doesn't do well is rapid changes in overall illumination. Specifically, the case where many flash photographs are being taken in a short time. That causes little problem with analog video, where frames are independent of each other. ...


Need 5 Frames of Interlaced Video

Started by Jeremy Smith in comp.dsp15 years ago 1 reply

Hi. Can anyone please point me at some public Web site that has a data file containing about 5 frames (i.e. 10 fields) of an interlaced video...

Hi. Can anyone please point me at some public Web site that has a data file containing about 5 frames (i.e. 10 fields) of an interlaced video sequence pulled from an NTSC television broadcast? I need this data for my research. Please respond by posting to the group. The e-mail address in the header does not work. Thanks.


Concurrent processes on the DM642?

Started by Anonymous in comp.dsp11 years ago 1 reply

I've been looking at similar sourcecode to some of the stuff I'm trying to do on the DM642 (video in -> process - > out) and noticed that in...

I've been looking at similar sourcecode to some of the stuff I'm trying to do on the DM642 (video in -> process - > out) and noticed that in some functions there seems to be some kind of concurrent processes - ie code within a 'while(1){...' loop that only captures video. How does this kinda thing work? How does it communicate status to the calling function? I assume this makes for a much qu


FFT of a video? (Caterpillars involved!)

Started by Alex Vaughan in comp.dsp14 years ago 1 reply

Hi, I'm trying to track the periodic movements of a caterpillar; in one behavior, it compresses its entire body regularly (period: 4s), and...

Hi, I'm trying to track the periodic movements of a caterpillar; in one behavior, it compresses its entire body regularly (period: 4s), and in another it has a peristaltic wave of compression that moves from tail to head (period:20 sec). I'd like to observe this by taking video, and doing a frequency analysis across time; the caterpillar itself doesn't move (much), so we're only looking...


Building the pendulum demonstrator

Started by Tim Wescott in comp.dsp3 years ago 8 replies

I show how I built the demonstrator for my systems & stability video. It's an electromechanical pendulum, and it's kewl -- or it was, until I...

I show how I built the demonstrator for my systems & stability video. It's an electromechanical pendulum, and it's kewl -- or it was, until I broke it making this video. https://youtu.be/YW33PVTYhdw -- Tim Wescott Wescott Design Services http://www.wescottdesign.com I'm looking for work -- see my website!


AGC for media (video) player software

Started by dv_ in comp.dsp6 years ago 4 replies

Hello, AGCs have been discussed here several times. However, there is one aspect I haven't seen mentioned here so far. There are many videos...

Hello, AGCs have been discussed here several times. However, there is one aspect I haven't seen mentioned here so far. There are many videos with a rather low sound level (especially VCR captures often have a very silent audio track). Also, it is unfortunately quite common that a video stream contains rather silent main content, interrupted by very loud ads. A replaygain prepass over videos ...


correlating rotated images with perspective

Started by Adam Chapman in comp.dsp12 years ago

Hi, I'm trying to make a vision-guided robot aircraft at uni and I want it to land on an 'H' shaped marker on the ground. The aircraft will...

Hi, I'm trying to make a vision-guided robot aircraft at uni and I want it to land on an 'H' shaped marker on the ground. The aircraft will only use the information from its mounted video camera to navigate. I have been looking into ways of identifying the helipad seen in the video, which will be rotated, scaled and have perspective. These properties will be used to determine the orie...


Recovering data (TMS320DM642)

Started by jerome in comp.dsp14 years ago 3 replies

Hi, Soon i will implement a video compression algorithm on DM642. I'd like to recover the compressed data, which will be stored in SDRAM,...

Hi, Soon i will implement a video compression algorithm on DM642. I'd like to recover the compressed data, which will be stored in SDRAM, in order to be able to replay the video on the PC. Can you tell me if Code Composer allows us to recover data stored in external memory and to save them in a file on the PC ? Does RTDX allow to do that ? Could you point me to some example codes ? ...


Real Time Video Rotation Using An FPGA.

Started by Alabama Engineer in comp.dsp14 years ago 2 replies

I would like recommendations on which FPGA to use (Xilinx vs. Altera vs. Actel) in an application which rotates a 640x480 real time video frame....

I would like recommendations on which FPGA to use (Xilinx vs. Altera vs. Actel) in an application which rotates a 640x480 real time video frame. I would also appreciate any pointers on rotation algorithms that I could use for this. Thanks in advance for all your help.


Video on tuning PID controllers

Started by Tim Wescott in comp.dsp3 years ago

Yet another video on tuning PID controllers has been tossed into the YouTube pool. ? https://youtu.be/drYO60z6_h4 -- Tim...

Yet another video on tuning PID controllers has been tossed into the YouTube pool. ? https://youtu.be/drYO60z6_h4 -- Tim Wescott Wescott Design Services http://www.wescottdesign.com I'm looking for work -- see my website!


Need recommendation: nonlinear video-frame warping

Started by axlq in comp.dsp11 years ago 4 replies

I'm sure this is a solved problem, but I don't know where to start looking. I have expertise in software and electronics, but DSP isn't my...

I'm sure this is a solved problem, but I don't know where to start looking. I have expertise in software and electronics, but DSP isn't my field of expertise, so I don't know what hardware is out there that will do the job I need. I am putting an R&D proposal together for my company, and one component of it involves real-time nonlinear transforms of a video signal. The transform, in re...


Video-equivalent of "pitch-shifting."

Started by Radium in comp.dsp12 years ago 48 replies

Hi: I started a new thread because the previous one started to go into tangent of digital vs. analog but was filled with emotions...

Hi: I started a new thread because the previous one started to go into tangent of digital vs. analog but was filled with emotions and personal vendettas rather than science and logic. So I changed the thread. Anyways, Adobe Audition and voice-changers allow the frequencies of an audio signal to be shifted w/out low-pass filtering or changing the tempo. There are two video-equivalents of...


video info below the carrier in analog channel?

Started by dtsao in comp.dsp11 years ago 6 replies

Hi, in an analog channel, I know the video carrier is 1.25 Mhz above the bottom of the channel. Also the color and audio info are 3.58Mhz and...

Hi, in an analog channel, I know the video carrier is 1.25 Mhz above the bottom of the channel. Also the color and audio info are 3.58Mhz and 4.5 Mhz above this video carrier. But I wonder, is there any info below the carrier, between the bottom of the channel and the 1.25Mhz? My guess is no, but I'm not sure.


Component Video (Low Res) conversion to RGB BITMAP possible using dsPIC?

Started by amr in comp.dsp10 years ago

My project basically involves being able to take screenshots from a medium-res component video signal (not HD.) Is a dsPIC capable of doing...

My project basically involves being able to take screenshots from a medium-res component video signal (not HD.) Is a dsPIC capable of doing that? In general, I'm trying to get a feel for the kind of horse power needed to do this task. I tried to find the Component specification to figure out what frequencies it runs at and so on, but I had no luck with that.