Billeder Af God Kvalitet

Sådan Tager Du Billeder Af God Kvalitet Nemt

Folk elsker at tage billeder af deres foretrukne begivenheder, men ikke alle af dem er gode til det. Nogle producerer billeder, der er sløret og indeholder visuelt uæstetiske egenskaber, såsom røde øjne og blænding. Selvom ikke alle har fotografering færdigheder af en professionel, kan de blive bedre. Brug fotografering tips i denne artikel for at øge din fotografering færdigheder.

Få mere at vide om, hvordan du fastgør et billede hurtigt. Vent ikke til dit emne for at tage en vis pause, dette kan ikke ske. Tag flere billeder, hvis du har brug for det. Ved at tage billeder hurtigt, vil du få naturlige udtryk og pauser. Hvis du venter for længe, dit emne vil sandsynligvis have en temmelig stiv og kunstig udtryk.

Hvis du planlægger at tage billeder udenfor, revurdere belysningen hver 10 minutter, som belysning er i konstant forandring. Juster din vinkel for at få det bedst mulige billede og belyse de funktioner, du forsøger at fremhæve. Planlægning på forhånd er meget vigtigt for at producere kvalitet fotos.

En af de ting, du kan gøre, når du tager billeder er at læne sig op ad noget for at opnå en bedre balance. Jo mere balance, du har, jo mindre bevægelse kameraet vil gøre, hvilket kan forbedre skarpheden af dine billeder. Bevar din balance, hvis du ønsker optimale fotografier.

Forstå og forudse den indvirkning, som vinden vil få på de billeder, du tager. For eksempel, hvis du planlægger at skyde blomster, undgå dage, hvor vinden er meget aktiv. Når blomster og planter er stabile, vil du have den bedste chance for at få den højeste kvalitet og opløsning i dit billede. I situationer, hvor du ikke har et valg, såsom bryllupper, har en beredskabsplan. Er der beskyttede områder, hvor vinden vil få mindre indflydelse?

En god fotografering tip, der kan hjælpe dig, er at tage et skridt tilbage fra dit arbejde nogle gange. Et billede, du måske ikke har som før, kan pludselig synes tiltalende for dig. Det er meget vigtigt at træde tilbage fra dit arbejde, så du altid kan have et nyt perspektiv.

En vigtig fotografering tip at huske på er at altid sørge for der er et klart fokuspunkt i dit fotografi. Uden et omdrejningspunkt, vil der ikke være meget der for at holde beskuerens interesse. Deres øjne vil bare vandre, og de vil hurtigt gå videre til det næste fotografi.

Forstå og Lær dit kamera at kende. Selv om dette lyder simpelt, mange mennesker har aldrig selv læst instruktionerne om, hvordan man betjener deres kamera. Få at vide og forstå de forskellige menuer og funktioner på hver knap på det, så når du skal bruge en bestemt funktion, du ved, hvor du finder det, og at kameraet kan udføre det.

Tag billeder af mærkelige og interessante ting, når du rejser. Mens du normalt kan springe over disse typer af skud, vil de ophidse vidunderlige erindringer om din rejse, når man ser gennem dem senere.

Tag noter, når du tager billeder. Når du ser på dine billeder senere, vil det være rart at se, hvor billedet blev taget, eller dine følelser, som du gjorde det. Brug en Notesblok til at skrive tal ud for billedernes beskrivelser.

Når du fotograferer små børn, er tid og tålmodighed din bedste ven. Børn lærer at "sige ost", når et kamera er fokuseret på dem, uundgåeligt skabe kunstige, falske smiler-eller værre. Ideelt set vil et barn blive behageligt at blive fotograferet, når presset til at "udføre" er fjernet. Du skal blot opfordre dem til at gå om deres normale aktiviteter og derefter følge dem rundt med dit kamera, klikke på, når de naturligt smil eller tydeligvis nyder deres omgivelser.

https://voresstoredag.dk

https://forevigt.dk

https://www.voresstoredag.net

https://www.fotograftilbryllup.dk

https://bryllupsfotograf.info

https://voresstoreja.dk

https://bryllupsfoto.voresstoredag.dk

https://blog.voresstoredag.dk/

Komme så tæt på emnet for dit emne.

De fleste moderne digitale kameraer har en Flash-komponenter, der automatisk udruller, når lyset er svagt. Dette er fint for casual Snapshots, men for noget mere professionelt, kan du prøve at investere i en type ekstern flash-enhed, der vil give dig en bred vifte af lys.

Sammensætning er en vigtig færdighed, du er nødt til at lære om og uddanne sig på. Som med noget kunstnerisk, dårlig sammensætning kan alvorligt forringe kvaliteten af arbejdet.

Når du lærer fotografering, på et tidspunkt skal du have en form for professionel instruktion. Self-undervisning kan kun få dig så langt. Hvis du ikke tager en klasse på fotografering, så prøv at blive involveret i fotografering samfund. Tal med og Spørg fagfolk til Råds; efter alt der er ingen bedre lærere i feltet end faktiske fotografer.

Tage oprigtig skud. I stedet for at optage billeder, så prøv at tage billeder af dit med familie på arbejde eller at gøre noget, de elsker. Når dit emne er behageligt de vil være mere tryg, og du vil ende med at få nogle unikke skud. Dette fungerer især godt, når de forsøger at fotografere børn.

Hvis det er muligt, undgå at bruge blitz, som du finder på de fleste kameraer i dag. Det har en tendens til at give emnet ' røde øjne ', og det fjerner en masse af skyggen, der kan skabe dybde i et billede. Hvis du er nødt til at bruge en flash, såsom en indendørs natlig skud, holde dit motiv væk fra vægge. På denne måde vil du ikke ende op med en grim sort skygge, der ligner en skitse.

Som nævnt før, folk elsker at tage billeder, men ikke alle tager dem godt. De billeder, nogle mennesker genererer, indeholder sløring, røde øjne og andre negative resultater. Alle kan blive en bedre fotograf med lidt hjælp. Ved at bruge fotografering tips i denne artikel, kan du tage bedre billeder.

Careful with audio resampling using FFmpeg

In my line of work transcoding videos for dr.dk/pirattv i use FFmpegextensively. I have written a tool in C# that automates this task and in doing so, i discovered that FFmpeg is not a good choice for downsampling audio. The downsampling does not suffer from aliasing because the signal is properly attenuated at the Nyquist frequency – but the quality of this lowpass filter is terrible. The problem lies with the lowpass filter which is by no means steep enough so it unnecessarily cuts a lot of high frequencies fairly far from the Nyquist frequency. The only good thing about the filter, is that the resampling is really fast. I have not found a setting in FFmpeg that forces it to use a better filter so i wanted to find a better way:

From looking at this awesome site i learned that one of the very best resamplers around: SSRC – is free and even open source! So now i treat the audio separately from the video and do all downsampling using SSRC which preserves the treble which is indeed audible when transcoding music.

Update: I ended up using SoX, because I needed more than just great resampling. SSRC is in theory slightly better but the difference is inaudible to me and SoX provides me with an array of additional possibilities.

Update II – FFmpeg now includes the SoX resampler – but only utilizes it if you tells it to – the default resampler is still the simple one with its limitations.
To use the better resampler from SoX, eg resampling to 44.1 kHz, add the following to your command line:

-af aresample=resampler=soxr -ar 44100

ProRes support in FFmpeg – I love it!

FFmpeg added support for ProRes in october 2011 – which made my life a little easier. The added support for ProRes closed a big gap for me as I quite often get exports in ProRes and need to transcode it into something more lossy like H.264 for usage on the web.
FFmpegs support for ProRes will also lead VLC in supporting ProRes in their upcoming 1.2 release. Great!
(Update: It was later renamed to version 2.0 and was released in february 2012.)

A quick note on how to trancode to Apple ProRes (often denoted APCN) using a recent build of FFmpeg:

ffmpeg -i input.mov -vcodec prores -profile:v NUMBER  output.mov

For different flavors of ProRes replace NUMBER with a number from zero to 3 where:
0 : ProRes422 (Proxy)
1 : ProRes422 (LT)
2 : ProRes422 (Normal)
3 : ProRes422 (HQ)

The following was taken from FFmbc’s wiki site:

The encoder behave differently based on 3 options:
-qscale < value > or -cqp < value >
Specify a fixed quantizer that will be used for every frame. This is a VBR encoding method.

If bitrate is not specified, the bitrate will be automatically chosen based on video resolution and will be similar to the reference encoder for the same profile.
-b < bitrate >
Specify a approximately constant bit rate to use during encoding.
444 encoding: add -pix_fmt yuv444p10 to your commandline options.

Update: ProRes 444 doesn’t seem to work, but people are working on a patch as learned from this thread:
http://ffmpeg.org/pipermail/ffmpeg-user/2012-September/009521.html
I must admit I haven’t used the codec lately, but people write that Final Cut Pro often gives the warning that ProRes files made with FFmpeg, are not optimized for FCP. All that means is, that the file wasn’t compressed using FCP but the file should work fine.

If you use the ProRes encoder, you might want to read this blogpost by the author Kostya.

Finding the best HTML5 player

I was looking for the best HTML5 player with Flash fallback and iOS support and stumpled upon the site VideoSWS – see what sucks. It’s a great source if you’re looking for a great HTML5 player. It confirmed my own little research which initially lead me to Mediaelement. After trying out MedieElement I had trouble getting it to perform inside a hidden block-level element – that becomes visible (like a fade) and I therefore turned my head towards the open source HTML player Projekktor which really rock.  Check out the end result here.

Optimal H.264 encoding for Flash and HTML5

During the years I have been in involved in broadcasting and web developement, I have done a lot of trial and error regarding encoding for the web. I have always used FFmpeg for the video part of the encoding, and recently improvements in FFmpeg has done the syntax much more straightforward, so let me show you how to make the best possible encoding when wanting to playback video on the web using HTML5/Flash:

First of all – find out what resolution you want to target. If you’re advanced, you will want to encode multiple resolutions so the server or the user can choose whichever resolution is best suited. However, in some cases it’s too complicated, so finding one target size that represents the best compromise, is often preferable.
Finding the right resolution is a matter of finding the right balance between visual quality and performance – the more pixels, the harder it is for the computer to decode and display the signal. My choice is 768 x 432 pixels in 1 megabit (plus audio). It gives a descent image – not far away from DVD quality, and just about all computers will display it without stuttering and without dropping frames. We will encode the audio so well, that it will be hard to tell it apart from the original; which will actually make the viewer perceive the image quality as being better than it is (I guess this report shows my point).

1-pass or 2-pass encoding?
So, when encoding we’re left with two choices: 1-pass or 2-pass encoding. 2-pass encoding is the obvious choice if you plan to stream your signal using a stream server like: Adobe FMS or Wowza using a protocol like RTMP. A 2 pass encoding ensures, that the stream has a fixed bitrate – but without the artifacts and drawbacks known from CBR (Constant Bitrate). This is only relevant when using a real stream server, since it makes it easier to do load balancing cause you always know how many streams each server can handle – which is usually limited to the network card in the server.

If you just plan to stream using a regular webserver – also known as progressive download, then you’re better of using 1-pass encoding since 1-pass is faster to encode (like 40% faster) and gives you a better visual quality in the same amount of data.

Let’s transcode!Now it’s time for the actual transcoding using FFmpeg. What I do is as follows:

#1 – decode the audio of the input video file to wav (uncompressed).
#2 – encode the wav file to AAC using Nero AAC.
#3 – encode  the video using FFmpeg
#4 – mux (combine) the video and audio together using MP4Box.

Update! Since FFmpeg now offers a good AAC encoder, it’s no longer necessary to use Nero’s AAC encoder. Thus you can skip step 1, 2 and 4 and go straight to step 3. All you have to do is to skip the -an parameter. Nero would however still be my choice.

I use Windows and the following works great:

Video encoding (size 768×432 pixels, 1 megabit. -tune film is the default, use -tune animation for non-film inputs):

Video encoding using 2-pass:
Pass 1:

ffmpeg -i “input.mov” -vf scale=768:432 -pass 1 -sws_flags lanczos -vcodec libx264 -preset slow -tune film -y -an -b:v 1000k -bufsize 2000k -f rawvideo NUL
ffmpeg -i “input.mov” -vf scale=768:432 -pass 2 -sws_flags lanczos -vcodec libx264 -preset slow -tune film -y -an -b:v 1000k -bufsize 2000k -f mp4 temp.mp4

Video encoding using 1-pass (the rest of the steps are the same for both 1-pass and 2-pass encoding):
ffmpeg -i “input.mov” -vf scale=768:432 -vcodec libx264 -preset slow -tune film -y -an -crf 22 temp.mp4

Audio encoding:
ffmpeg -i “input.mov” -y -ac 2 -f wav temp.wav
neroAacEnc -q 0.35 -if temp.wav -of temp.m4a

Muxing together:
mp4box -add temp.m4a#audio “out.mp4″
mp4box -add temp.mp4#video “out.mp4″

Voila! You have the best H.264 encoding in town!

Notice that I use “-f rawvideo NUL” for my first pass. This tells FFmpeg not to output an output file since all we want to do is to build a stat file for the second pass. This speeds up the first pass a bit. Also notice the -an parameters which tells FFmpeg not to encode audio since we do that with Nero instead – again a minor performance gain.

A great bonus of using MP4Box is that it places the moov atom in the beginning of the file. This causes the file to play immediately when served using progressive download. FFmpeg on the other hand, places the moov atom in the end of the file – hence you have to download the whole file before being able to start it, because only the moov atom can tell the player how to interprete the H.264 file. If you want to know the deeper explanation behind this, you can get it here and here.
(Update august 2013: FFmpeg now has some support for faststart)
When doing the single pass video encoding, we use the CRF parameter instead of a fixed data rate. CRF means constant quality mode also known as constant ratefactor and denotes the quality of the encoding. You assign the CRF parameter a number between 15 (best) and 31 (worst) – and use decimals if you like. I often use 22, which gives a fairly small file size while maintaining a great visual quality.

Why not let FFmpeg encode to AAC? Well, in short, because FFmpeg is lacking a good AAC encoder – but more on this issue in a later blog post. Update! This has now changed and the built in AAC encoder is comparable with the Nero AAC encoder.

Merging VOB files

A couple of years ago I was faced with the challenge of transcoding a DVD into an optimized H.264 file for usage on the web. First of all I had to remove the copy protection using DVD Decrypter. Now I had a bunch of VOB (Video Object) files. A DVD movie is one continuously MPEG-2 file in a transport stream. But for simplicity the VOB has a max limit of 1 Gb, so before I could input the VOB files into FFmpeg, I had to find a way to merge the VOB files into one file. Thankfully this is easy, all you have to do is to merge the files – and you can use Windows’ copy function for this – as long as you remember to set the binary switch (/b):

copy /b vts_01_2.vob + vts_01_3.vob + vts_01_4.vob + vts_01_5.vob mergedfile.vob

I omitted the first file vts_01_1.vob since it contained the menu.

New open source RTMP streaming server in town!

If you want to set up your own streaming server on a cheap VPS solution – which can be bought down to 10 dollars a month – then your only option is Red5, since Wowza and Adobes FMS both cost quite a bit of money.

However it seems like Red5 is not all that popular, so I was thrilled to learn, that a guy called Rarut is making a RTMP streaming module for the powerful webserver Nginx. He just announced MP4 support for his module, so this is definitely worth a look!