20130515

Nerd Review: IPhone 4 as Video Camera

English Warning: this is a nerd review i.e. the potential for too much information overload may occur while reading portions of this review! Eyes glazing over while vaguely remembering your first encounter with a geek or nerd may occur — to prevent this, please look at the videos.

Attention: the first video has a faint recording of several women speaking either Gujarati or Hindi, or Cantonese or Mandarin. If you are able to understand either languages, then please determine which language they are speaking and the content of their chatter.

中文(简体)警告:这是一个书呆子审查,即潜在的太多信息超载可能发生,而读这篇评论的部分!同时依稀记得你第一次遇到一个怪胎或可能发生的书呆子 - 防止眼睛呆滞,请看看视频。

注意:第一视频有几个女人讲古吉拉特语或旁遮普语,粤语或普通话淡淡的记录。如果你是能够理解两种语言,那么请确定哪种语言他们说话的内容,他们的唠叨

中文(繁體)警告:這是一個書呆子審查太多信息超載的潛力,即可能發生在讀這篇評論的部分!同時依稀記得你第一次遇到一個怪胎或可能發生的書呆子 - 防止眼睛呆滯,請看看視頻。

注意:第一視頻有幾個女人講古吉拉特語或旁遮普語,粵語或普通話淡淡的記錄。如果你是能夠理解兩種語言,那麼請確定哪種語言他們說話的內容,他們的嘮叨

ગુજરાતી ચેતવણી: આ સમીક્ષા ભાગ વાંચતી વખતે ખૂબ માહિતી ભારને માટે સંભવિત એટલે કે એક nerd સમીક્ષા થઇ શકે છે! અસ્પષ્ટ એક રુચિ ધરાવો અથવા nerd આવી શકે છે સાથે તમારા પ્રથમ એન્કાઉન્ટર યાદ છે જ્યારે ઉપર આંખો ગ્લેઝિંગ - આ રોકવા માટે, વિડિઓઝ જોવા વિનંતી.

ધ્યાન છે: પ્રથમ વિડિઓ ગુજરાતી અથવા પંજાબી, અથવા કેન્ટોનીઝ અથવા મેન્ડરિન ક્યાં બોલતા અનેક મહિલાઓ એક હલકા રેકોર્ડિંગ છે. તમે ક્યાં તો ભાષા સમજવા માટે સમર્થ હોય, તો પછી તેઓ બોલતા અને તેમના પપડાટ સમાવિષ્ટ છે, જે ભાષા છે તે નક્કી કરો

हिन्दी चेतावनी: यह इस समीक्षा के अंश पढ़ने के दौरान बहुत अधिक जानकारी अधिभार के लिए क्षमता यानी एक बेवकूफ की समीक्षा होने पर हो सकती है! थोड़ा एक geek या बेवकूफ उत्पन्न हो सकता है के साथ अपनी पहली मुठभेड़ को याद करते हुए अधिक आंखें ग्लेज़िंग - इस को रोकने के लिए, वीडियो देखने कृपया.

ध्यान दें: पहला वीडियो गुजराती या पंजाबी, या केनटोनीज या मंदारिन तो बोल रहे कई महिलाओं के एक बेहोश रिकॉर्डिंग है. आप या तो भाषा को समझने में सक्षम हैं, तो वे बोल रहा है और उनके बकवास की सामग्री रहे हैं जो भाषा का निर्धारण कृपया


In this review, I'll be discussing the finer points of the use of a iPhone 4 as a video camera. At some point in the discussion, the Quicktime data of the audio and video stream of the movie may be displayed. According to Apple, display of said data may be subject to their copyright coverage. When I get the email from Apple to seize and desist, I'll let you know.

In the meantime, let's see how the iPhone works as a video camera.

First off, the video camera in the iPhone 4 is based on a 5 MP (2592 × 1936 pixels) camera but uses the 1920 x 720 format of Quicktime using the mpeg-4 standard of H264 for video and AAC for audio. This means the video is crisp and clear, and the audio quality is CD quality.

The camera is based on the backside illumination (BI) sensor made by Omnivision Technologies. This sensor makes use of wavefront coding created by radar engineer Edward Dowski and his thesis adviser Thomas Cathey at the University of Colorado in the United States in the 1990s. Because universities were yet to be business-savvy, both Dowski and Cathey formed CDM-Optics, which was acquired by Omnivision in 2005. Wavefront coding was designed to extend the depth of field of a digital imaging system such as a video camera.

As a result of the BI sensor in the iPhone 4, the video camera demonstrates extended depth of field when compared to other smartphone video cameras. However, the camera proper tends to ramp down the brightness on images focused on the sun. This makes it difficult to photograph sundogs, which helps to test camera firmware's ability to compensate properly when pointed at a very bright point of light (the sun).

Thus, the video camera is equally sensitive to low-light conditions as the camera proper but not to intense points of light such as the sun and different types of lamps. As well, to properly adapt such exceptional light conditions, the user is forced to download an app to give it the same qualities of better thought out camera optics and firmware.

Overall, the video quality displayed is more than adequate. Here is information of the file format for the Quicktime MOV format displayed by the Linux app, mediainfo:

$ mediainfo 1327386B-D90A-4115-A82C-C640CAF883F4.MOV
General
Complete name : 1327386B-D90A-4115-A82C-C640CAF883F4.MOV (Apple uses a UUID-like identifier to uniquely name each file iOS creates. My guess is this UUID becomes date and time of file creation.)
Format : MPEG-4
Format profile : QuickTime
Codec ID : qt
File size : 80.1 MiB
Duration : 1mn 3s
Overall bit rate : 10.6 Mbps
Recorded date : 2013-05-10T11:21:40-0700 (The date area is copied to converted MP4 and MPEG files, thus retaining the local and UTC date and time. it is duplicated in the Apple quicktime API information below.)
Encoded date : UTC 2013-05-10 18:21:40
Tagged date : UTC 2013-05-10 18:21:53 (According to this tagged date, it takes 13 seconds to tag the resulting video file.)
Writing application : 6.1.3
Writing library : Apple QuickTime
Model : iPhone 4
: +49.2045-122.8897+041.860/ (This is the GPS location of the iPhone 4 during filming of the video. It is repeated again under the Apple quicktime API information listed below.)
Make : Apple
com.apple.quicktime.make : Apple (Apple quicktime API information)
com.apple.quicktime.creationdate : 2013-05-10T11:21:40-0700
com.apple.quicktime.location.ISO : +49.2045-122.8897+041.860/
com.apple.quicktime.software : 6.1.3
com.apple.quicktime.model : iPhone 4

Video
ID : 1
Format : AVC
Format/Info : Advanced Video Codec
Format profile : Baseline@L3.1
Format settings, CABAC : No
Format settings, ReFrames : 1 frame
Codec ID : avc1
Codec ID/Info : Advanced Video Coding
Duration : 1mn 3s
Bit rate mode : Variable
Bit rate : 10.5 Mbps
Width : 1 280 pixels
Height : 720 pixels
Display aspect ratio : 16:9
Frame rate mode : Variable
Frame rate : 29.970 fps
Minimum frame rate : 28.571 fps
Maximum frame rate : 30.000 fps
Color space : YUV
Chroma subsampling : 4:2:0
Bit depth : 8 bits
Scan type : Progressive
Bits/(Pixel*Frame) : 0.381
Stream size : 79.6 MiB (99%)
Title : Core Media Video
Encoded date : UTC 2013-05-10 18:21:40
Tagged date : UTC 2013-05-10 18:21:53
Color primaries : BT.709-5, BT.1361, IEC 61966-2-4, SMPTE RP177
Transfer characteristics : BT.709-5, BT.1361
Matrix coefficients : BT.709-5, BT.1361, IEC 61966-2-4 709, SMPTE RP177

Audio
ID : 2
Format : AAC
Format/Info : Advanced Audio Codec
Format profile : LC (This is the Low Complexity version of AAC, which is technical jargon for simplest version.)
Codec ID : 40
Duration : 1mn 3s
Bit rate mode : Constant
Bit rate : 64.0 Kbps
Channel(s) : 1 channel
Channel positions : Front: C (Sound is recorded as thought it is front and centre.)
Sampling rate : 44.1 KHz
Compression mode : Lossy
Stream size : 496 KiB (1%)
Title : Core Media Audio
Encoded date : UTC 2013-05-10 18:21:40
Tagged date : UTC 2013-05-10 18:21:53



No comments: