422 Colorspace, How to measure.

I’m still trying to wrap my head around color space difference and I do not mean in technical terms but in realistic “can you see it” terms. I understand that 4:2:2 has more color than 4:2:0 and 4:4:4 has more than 4:2:2. SO the question is can you really tell the difference and I mean can the average person tell or do you need a DP, ASC being critical on a big screen to show you the difference?
Also what does compression do? If I shoot 1080p 4:4:4 and compress to 1080p h.264 at 6Mbps do I still get that benefit? Or compressed to HD for broadcast?
Lastly how do you measure this color space? Are there tools out there tha can tell you if you have a clip that has been shot at a certain color space?
Is there a wow factor? I guess this is the true question. So many people are obsessed with color space. Should I be too? Thanks.

The whole point of limiting the chroma is that you can get away with it. It's not supposed to be noticeable, and without an identical 4:4:4 copy to compare with, you're unlikely to spot it. The only time it's really a problem is when you need to process the image, for example if you are doing green screen compositing.
There's no reliable way to detect color sampling. If the source clip had a lower color sampling rate than the codec it was transcoded to, you may possibly be able to detect the missing values (I haven't actually tried this though). You won't be able to detect if the values have been clipped in the colorspace conversion though.
I think this is one of those things that people worry far too much about. There are situations where it's important but I always favor a lower compression ratio over a higher color sampling rate.

Similar Messages

How to measure the baseline of a noisy, pulsed signal

Hi
I am measuring the torque exerted by a large motor on a shaft using a load cell and lever arm. The shaft runs at approx 150 rpm. I have attached a drawing that shows the output I get. This is a test rig.
I have written some code that measures the maximum peak out of a group of approx 5 peaks and writes this to a shift register. This gives me an idea of the maximum torque "spike".
I also wish to measure the baseline torque (due to the bearings in the machine). Even when highly filtered (my noise filter is set to 49Hz) the signal exhibits this noise which is probably due to vibration in the system. The signal is zeroed when the motor is not running.
Does anyone have an ideas on how to measure the "baseline" torque? The large spike in torque prevents me from doing a running average. Can anyone think of a way of averaging just the noisy part of the signal to get an average value? I aim to to subtract the average baseline torque from the peak value to get an idea of the torque due to the event which causes
the spike.
Any help would be greatly appreciated.
Many thanks.
Attachments:
drawing of torque signal.gif ‏26 KB

Thanks for the reply. I understand what you are saying. However, I might have to modify my method for measuring the peaks if I choose to implement your idea. I have taken a screenshot of my "peak finder" code and attached it.
Bascially, the reset terminal is wired to a timer which outputs a pulse every few seconds. This resets the vi (a standard NI one I think) and sets the peak magnitude back to zero. This way, I am windowing the signal and measuring the maximum peak in every window. This is what I need to do.
So I could use a logical filter to feed data to the running average only if;
the amplitude of the signal is less than a certain threshold
and if the current value has similar low peaks either side of it
How would you construct the code to delay the evaluation so that the values in front and behind of the current data point can be analysed?
thanks again
Attachments:
peak_find_screenshot.jpg ‏45 KB

How to measure the performance of Extractor

Hi,
How to measure the time taken to by the extractor when executed from rsa3 for a given selection?
Lot of threads speak about ST05... but these transactions are too granular to analyse.
How to get the overall time taken.i need the overall time taken and the time taken by the individual SQL statements... please provide specific pointers.
Thanks,
Balaji

Maybe SE30 can help you....
Regards,
Fred

How to measure the performance of sql query?

Hi Experts,
How to measure the performance, efficiency and cpu cost of a sql query?
What are all the measures available for an sql query?
How to identify i am writing optimal query?
I am using Oracle 9i...
It ll be useful for me to write efficient query....
Thanks & Regards

psram wrote:
Hi Experts,
How to measure the performance, efficiency and cpu cost of a sql query?
What are all the measures available for an sql query?
How to identify i am writing optimal query?
I am using Oracle 9i... You might want to start with a feature of SQL*Plus: The AUTOTRACE (TRACEONLY) option which executes your statement, fetches all records (if there is something to fetch) and shows you some basic statistics information, which include the number of logical I/Os performed, number of sorts etc.
This gives you an indication of the effectiveness of your statement, so that can check how many logical I/Os (and physical reads) had to be performed.
Note however that there are more things to consider, as you've already mentioned: The CPU bit is not included in these statistics, and the work performed by SQL workareas (e.g. by hash joins) is also credited only very limited (number of sorts), but e.g. it doesn't cover any writes to temporary segments due to sort or hash operations spilling to disk etc.
You can use the following approach to get a deeper understanding of the operations performed by each row source:
alter session set statistics_level=all;
alter session set timed_statistics = true;
select /* findme */ ... <your query here>
SELECT
         SUBSTR(LPAD(' ',DEPTH - 1)||OPERATION||' '||OBJECT_NAME,1,40) OPERATION,
         OBJECT_NAME,
         CARDINALITY,
         LAST_OUTPUT_ROWS,
         LAST_CR_BUFFER_GETS,
         LAST_DISK_READS,
         LAST_DISK_WRITES,
FROM     V$SQL_PLAN_STATISTICS_ALL P,
         (SELECT *
          FROM   (SELECT   *
                  FROM     V$SQL
                  WHERE    SQL_TEXT LIKE '%findme%'
                           AND SQL_TEXT NOT LIKE '%V$SQL%'
                           AND PARSING_USER_ID = SYS_CONTEXT('USERENV','CURRENT_USERID')
                  ORDER BY LAST_LOAD_TIME DESC)
          WHERE ROWNUM < 2) S
WHERE    S.HASH_VALUE = P.HASH_VALUE
         AND S.CHILD_NUMBER = P.CHILD_NUMBER
ORDER BY ID
/Check the V$SQL_PLAN_STATISTICS_ALL view for more statistics available. In 10g there is a convenient function DBMS_XPLAN.DISPLAY_CURSOR which can show this information with a single call, but in 9i you need to do it yourself.
Note that "statistics_level=all" adds a significant overhead to the processing, so use with care and only when required:
http://jonathanlewis.wordpress.com/2007/11/25/gather_plan_statistics/
http://jonathanlewis.wordpress.com/2007/04/26/heisenberg/
Regards,
Randolf
Oracle related stuff blog:
http://oracle-randolf.blogspot.com/
SQLTools++ for Oracle (Open source Oracle GUI for Windows):
http://www.sqltools-plusplus.org:7676/
http://sourceforge.net/projects/sqlt-pp/

Can you tell me how to measure audio signal frequency in measurement studio with visual basic 6.0?

I'd like to measure two differential input signal(I.e. A+ and A-),below is two test projects,
1.connect A+/A- to PCI 6052E card's ACH0/ACH8 ,and refer to GND for testing
2.connect respectively A+/A- to PCI 6052E card's ACH0/ACH8 for testing
Could you tell me the details of the second project?and give me a illustration in measurement studio with visual basic 6. 0 about the second?
In addition,I would like to measure the audio signal frequency,could you give me a illustration in measurement studio with visual basic 6.0?
Wait for your reply!

Dear kelven,
Thank you for contacting National Instruments.
To address your question, there are Analog Input shipping examples that demonstrate how to measure an analog input differentially, as you specify in (2).
As for measuring the audio signal frequency, you may want to check out the following KnowledgeBase. The link is:
http://digital.ni.com/public.nsf/websearch/4b08380530d72d3b86256340004c3005
Let me know if you have any further questions or if this does not resolve your issue.
Thanks again and have a great day!
Chad AE
Applications Engineer - National Instruments

How to measure the size of a table ?

Dear all,
May I know how to measure the size of a customized table. I have a list of customized table and I want to monitor the growth of the table size on daily basis.
Please advise how do I do it.
Your advice and input will be appreciated.
Thanks.
Regards,
Kent

Go to DB02 -> Detailed Analysis -> Enter the table name under "Object Name" -> Click history to see the changes in size by day.
Regards
Juan

How to measure the size of a string

windows app store how to measure the size of a string?
string str = "Hello word windows app store";

if you need the actual width the string occupies in pixels than use (see
this MSDN link for more details):
Graphics.MeasureString(String, Font)
if you only need the "length" of the string i.e. no. of characters than use (see
this MSDN link for more details):
str.Length
dont forget to bing / google :)
hope this helps!
Graphics.MeasureString(String, Font) can not use in windows store app.
TextBlock has Measure()
method, as following:
Size MeasureString(string content, Size availableSize, double fontSize, string fontFamily="Segoe UI")
    TextBlock tb = new TextBlock();
    tb.TextWrapping = TextWrapping.Wrap;
    tb.Text = content;
    tb.FontFamily = new Windows.UI.Xaml.Media.FontFamily(fontFamily);
    tb.FontSize = fontSize;
    tb.Measure(availableSize);
    return tb.DesiredSize;
Test:
string str = "Hello word windows app store";
Size size = MeasureString(str, new Size(800, 600), 40);

How to measure the InfoCube size?

can any body help me regarding this
how to measure the info cube size?

1. use transaction se16, infocube table /../f[infocube name] and /.../e[infocube name], count 'number of entries' - total records
use transaction db02 tablename infocubename - size in bytes
Re: how can we measure the info cube size
2. asap methodology
Re: Lifecycle Implementation
hope this helps.
regards
harikrishna N

How to measure the size of an object written by myself?

Hi all,
I'm going to measure the performance on throughput of an ad hoc wireless network that is set up for my project. I wrote a java class that represents a particular data. In order to calculate the throughput, I'm going to send this data objects from one node to another one in the network for a certain time. But I've got a problem with it- How to measure the size of an object that was written by myself in byte or bit in Java? Please help me with it. Thank you very much.

LindaL22 wrote:
wrote a java class that represents a particular data. In order to calculate the throughput, I'm going to send this data "a data" doesn't exist. So there's nothing to measure.
objects from one node to another one in the network for a certain time. But I've got a problem with it- How to measure the size of an object that was written by myself in byte or bit in Java? Not.

How to measure a current signal with NI 6211?

How to measure a current signal with NI 6211?

Hi Clecio,
This is a charge accelerometer. It is different from the IEPE accelerometers that outputs a voltage signal.
You need a charge amplifier. Then according to the charge amplifier output we can select an appropriate module to measure the signal.
It is not possible to measure charge accelerometers with NI 9234 directly.
Best Regards,
Rodrigo Schneiater
Application Engineering
National Instruments Brazil
If this information was useful, please click in the 'KUDOS!' beside.

How to measure torque on a DC motor using Multisim?

Hello,
I would like to know how we measure torque on a DC motor using Multisim Education edition.
I've searched for the component, "eddy current load brake", but could not find it. Is that component in Multisim?
Thank you,
Neil

Hi,
Please refer to this forum post.
http://forums.ni.com/t5/Circuit-Design-Suite-Multisim/PM-DC-Motor-Model-Trouble/td-p/1931859
Hope this helps.
Regards,
Tayyab R,
National Instruments.

How to measure path area in Illustrator CC?

How to measure path area in Illustrator CC?
For example I draw a rectangular, how do I get it's area size?
Thanks!!!

I also would like to know it... Push

How to measure CPU utilization from Oracle AWR

Hi All,
How to measure the cpu usage % from the AWR reports.
Oracle : 10.2.0.3
OS : AIX 5300-12-02
I see the top 5 waited events listing CPU time in it.
Top 5 Timed Events Avg %Total
~~~~~~~~~~~~~~~~~~ wait Call
Event Waits Time (s) (ms) Time Wait Class
CPU time 98,655 40.0
Is it mean that the CPU utilization is full to its 100%. Is there any other way to measure how much an oracle instance is utilizing the CPU ?
Please advice.
TIA,
Nv

Hi,
Check this script, if possible run in toad.
col LastCallET format 99,999
col cpumins format 99,999
col status format a1 trunc
col module format a20
col username format a15
col logontime format a12
col machine format a15 trunc
col sid format 9999
select * from (
select 'P',s.sid, s.status, t.value/100/60 cpumins ,
     floor(last_call_et/60) "LastCallET",
     to_char(s.logon_time,'mm/dd hh24:mi') logontime,
     s.username,s.process, p.spid, s.module , s.machine, s.sql_hash_value
from v$sesstat t, v$session s, v$process p
where t.statistic# = 12
and s.sid = t.sid
and s.paddr = p.addr
and s.type = 'USER'
and s.sql_hash_value != 1425819161
union
select 'N',s.sid, s.status, t.value*-1/100/60 cpumins ,
floor(last_call_et/60) "LastCallET",
to_char(s.logon_time,'mm/dd hh24:mi') logontime,
s.username,s.process, p.spid, s.module , s.machine, s.sql_hash_value
from v$sesstat t, v$session s, v$process p
where t.statistic# = 12
and s.sid = t.sid
and s.paddr = p.addr
and s.type = 'USER'
and s.sql_hash_value != 1425819161
and t.value < 0
order by 4 desc)
where rownum < 11
Regards,
Satya.

How to measure the task instance size

I am trying to understand how to measure the custom task instnace size that was occupied in the cache repository. Is there a way to obtain the size (in KB s ) in lighthouse 4.1 +sp5. Please help.

Hi, Luiz!
In order to estimate the instance size, you will have to sum up all the instance variables size.
From the practical prospective it may be difficult to use the algorithm in cases when your instance variables are not simple types.
For already existing instances, you can look the instance size in the database:
An instance is just a java object, that is serialized as a byte[] and stored in the engine database, PPROCINSTANCE table, column INSTDATA.
You can write a simple program (either java or SQL plus) that would read the instance from the BLOB and measure the size.
And yes, with large instances you can have performance problems.

How to measure/estimate Bias of the signal

Dear Sir
I am performing the FFT of the signal which collect in real time from the hall effect current tranceducer SCT-013-005. I need to measure/estimate bias of this signal. Can you please guide me how can I do that. (Attached is my vi which is developed in LabVIEW 2012)
I shall be thankful to you for your attention and consideration.
Kind Regards
Urfee
Solved!
Go to Solution.
Attachments:
How to measure Biase of the signal.vi ‏930 KB

Hi tronoh,
what about using the "Basic Averaged DC&RMS" function on your periodic signal?
Best regards,
GerdW
CLAD, using 2009SP1 + LV2011SP1 + LV2014SP1 on WinXP+Win7+cRIO
Kudos are welcome

422 Colorspace, How to measure.

Similar Messages

Maybe you are looking for