hi, all,
I am a little confused here. What is the difference between MPEG-2 AAC
and MPEG-4 AAC? They all have main profile, LC. Can I see them just as
different profiles? Is there any difference in the bit stream format?
Do they require different decoders?
Also the licensing, does MPEG-4 AA...
Hi,
as mentioned in the subject line, I am looking for a MPEG-2 to MPEG-4
converter, which is implemented in hardware. AFAIK, only
software-based solutions are available.
Thanks for any help,
Herbert
...
Hallo all,
I am Monica from Germany working on Digital Video Broadcasting(DVB).I
must implement a MPEG-2 frame generator in the VHDL.But to my surprise
I couldnt find anything realted to MPEG-2 frame structure and low level
MPEG-2 signalling details.
Is MPEG-2 a poprietary standard?If any...
Hi all,
Need a bit of guidance. I am planning to do a small project out
of my own interest and learning. I have choosen to implement an Mpeg
encoder/deocder.
Planning to provide support for both mpeg 2 and 4.
But i am stuck at one point. The ISO standard specs cost around 140 $
eac...
Hi
I am in need of a MPEG/H.264 codec in matlab. I want to play with the
compressed bitstream i.e. headers , motion vectors ,VLCs etc.
I need to convert a video into mpeg bitstream .... and then put my
watermark in this compressed domain.
It would be great if anyone could provide a solution(pre...
I want to make a demo application for IPTV based on MPEG4 or MPEG2. I have
basic understanding of MPEG2 and MPEG4.
I need help: How I can read packets from MPEG file in C or C++
Can any one suggest me beginner's tutorials for Implementing MPEG in
C/C++ or any other language. OR any open sourc...
Hi all,
I am new to the field of DSP/Video Compression. I wanted to learn MPEG
4 Video Compression standard in particular as it is required in my
current project which is about Live Video streaming using RTSP/RTP
protocol on the internet using MPEG 4 codec.
I have read some articles/ISO st...
Hello,
Suppose you have a surveillance project on which two 4-CIF NTSC
streams (704 x 480) @ 15 fps have to be encoded for network streaming
and for storage, and that the network bandwidth is up to 2 Mbps.
Also, the encoder has to run on an embedded platform (Blackfin, for
example).
Whic...
Hi all.
I have used MPGWRITE with some success to make small MPEG movies from
data I manipulate and plot with matlab.
Now I want to put a sound track with the movie, but have a very vague
recollection of having seen somewhere (I can't find any mention of it
now) that MPGWRITE does not ...
Hello,
Supose you need to compress two independent video streams, each one being
4-CIF (704 x 480) at 15 fps for a surveillance application, and that they
(both) need to be steramed thru the same network but the max bitrate that
you have for that streaming function is 2 Mbps.
Which one o...
I am unable to understand that why we go for horizontal or vertical scan at
all while decoding MPEG-4 bitstream? I guess Zig-Zag scan is the best then
why not only ZIG-ZIg. Is there any more compression by horizontal or
vertical scan? According to mpeg-4 standard zig-zag scan is done only when
ac pr...
Hi everyone,
I'm currently investigating some audio-codecs used in radio-broadcasting.
Apart of the technical issues involved there is obviously the topic of
licencing.
On the MPEG FAQ I found a contact at Philips for MPEG layer 2:
w.l.vanderkruk@patents.corp.philips.com
Unfortunately...
Hi all,
I am reading Fogg's MPEG FAQ.
(http://bmrc.berkeley.edu/frame/research/mpeg/mpeg2faq.html)
The FAQ have several diagrams about skipped block and motion vector.
How to determine the skipped block in B frame?
And what syntax in video stream describe it?
e.g. If I have a picture seq...
Hi there, Wondering if I can get free MPEG 4 / H.263 source code
(written in java/C/C++/perl) for learning purpose. I'm a coding
theorist & would like to apply some of the enhancement techniques at
the decoder. Regards,
-KK
...
Hi all.
I have just spent a few days making some small MPEG movies that
illustrate certain wave propagation phenomena. First of all,
while I have made movies for my own use for the last 7 or 8 years,
being able to actually make MPEG movies from time-domain simulated
data has opened up a wh...
Hi all,
I am reading MPEG source code. I found all the Y U V are initialized to
128. Why?
Before the I picture transform, the source picture was subtract from a
"virtual" reference picture(Y U V are all 128). What's it mean?
Any suggestions will be appreciated!
Best regards,
Davy
...
Is there a public source code repository of MPEG-7 visual descriptors?
Recently I am extracting visual features from video files, such as
Color Moment, Edge Histogram, etc.
I need some reference source code.
How can I get it?
Any help appreciated. Thanks in advance.
...
Hello.
Is there a free/shareware MPEG player with the ability to allow me to save
each decompressed frame as a JPEG/bitmap/etc. file? I need the ability to
save 10 consecutive frames.
Please respond to the newsgroup. The above e-mail address does not work.
...
Hi guys,
I'd like to know if some of you have already implemented MPEG (2 or 4)
video compression on DSP. What free source codes have you used ?
Could you give me some links to good free source codes ?
I've searched on the net but haven't found anything really good.
Thanks for your help.
...
I'm starting to look at a home project for creating a stand alone
webcam server. What I'd like to do is have 3-4 usb inputs for webcams,
convert the inputs into mpeg and send the data out an ethernet port. I
want to be able to support real-time (or close to it) video processing
and run a web ser...
I am trying to generate a test waveform which is compatible with the
ATSC standard. I am obtaining the MPEG packets from a TV clip obtained
from the web. I am ensuring that the MPEG packet frame rate of the
transport stream packets is compatible with the ATSC standard. The
waveform is converted ...
Davy wrote:
> Hi all,
>
> I heard that MPEG2 and MPEG1 use same compression methods.
>
> MPEG2's MP@LL and MPEG1 are all 4:2:0, 352*288*30. But MPEG2's MP@LL is
> 4Mbit/s and MPEG1 is 1.5Mbit/s. Why they have different bit rates?
>
> And if I want to do 352*288*30 video compression. ...
Hai all,
I have some doubts about how we read the data from MPEG file.
1) Do we read Audio and Video simultaneously ?
Or do we read one after another? Is free source code available to do
so?
2) While we are reading the Video data, do we read them frame by
frame or Block by Block (Macro...
I try to use wavread() function to open/read .wav reference files for
AAC (MPEG-2 AAC) compliance test provided by ISO/MPEG (ISO/IEC
13818-4). But I got the error message "Data compression format (Format
#65534) is not supported". However, there is no problem for Adobe
Audition and Microsoft Win...
Hi all,
I want to implement a encoder deal with I and P frame.
So only one reference frame is stored for motion search.
Is it the reconstructed forward frame?
But the MSSG (http://www.mpeg.org/MPEG/MSSG/) encoder's full search
function require 2 frames.
Its integer full search is based o...
Hi
I'd appreciate a sanity check on my back-of-the-envelope calculation
of the number of IDCTs needed in an MPEG decode.
If we have PAL 704x480 at 25 fps divided into 16x16 macroblocks, then
we have 1320 macroblocks.
If we are using YUV422 then each 16x16 macroblock has 4 8x8 blocks for
...
Hello,
DOes anyone know of any efficient methods to compress parts of a video
screen where perhaps motion is going on, ie a desktop playing an mpeg in
the corner?
Thanks
...
Hello.
Is there any good book that explains MPEG2, MPEG4, H.264, AAC
algorithms and implementations?
Or, any website would be great too.
Thanks!
Jack
...
On 1 Oct 2005 19:45:56 -0700, "Radium" wrote:
> dpierce@cartchunk.org wrote:
>
> > WAV is simply a specific container format for audio information.
> > WAV files can hold linear PCM, non-linear PCM such as A-law or
> > u-law, encodings such as MPEG, AC-3 and such.
> >
> > Thus, if ...
On 18 Feb, 23:18, Jaime Andres Aranguren Cardona wrote:
> Hello,
>
> Talking about video codecs, specifically Theora (www.theora.org) and
> M-JPEG2000, how do they compare in terms of compression ratio for a given
> quality?
Well, I've seen discussions that suggest JPEG2000 can compa...
thanks guido, that was illuminating but I made a mistake while framing
the question. it should have read why DCT for video compression as in
mpeg. I am sorry, but does it change your answer?
...
> Hi all,
>
> Does anybody know anything about the YMagic video platform offer? Their
> advertisement suggests they offer their DM642 cards with a free MPEG4
> library ( http://www.ymagic.com/overview.html ). Does anybody have
> experience with it? Is the library really free? What is the video...
Hi Guys,
Can anyone explain me How is MDCT different from basic DCT? how does
MDCT achieve Time Domain Alias Cancellation ( TDAC ) which is useful in
MPEG AUDIO compression.
TIA.
cheers.
Bhanu
...
Hi all,
I am reading MPEG-2's spec. It has a VLC coded_block_pattern_420. The
spec said we can get cbp from coded_block_pattern_420. But what's cbp's
function? Is it a important parameter?
Any suggestions will be appreciated!
Best regards,
Davy
...
i2genius.com wrote:
> What is the common MP3 coder? I don't need details, (although a url
> relating to a detailed specification may be handy in the future), but
> is it a: sub-band coder? Analysis by sythesis such as multipulse or
> celp? sinusoidal? Something else?
I don't know the ...
Hi Bernie,
Thank you ;-)
I cannot catch your idea. Is it for decoder?
And I am considering encoder :-)
I found rate control is the most difficult part of the mpeg encoder
design.
Any suggestions will be appreciated!
Best regards,
Davy
...
Hi all,
Has anyone achieved D1@30fps encoding on BF561 processor? And does
splitting the code into different core's will help increase the frame
rate?
We are running at D1@10fps. Any algorithm implementation, approach ,
guidence will be helpful regarding this.
Thanking you.
Warm Regards,
...