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Europeana was launched in 2008, with the goal of making Europe’s cultural and scientific heritage accessible to the public. The project is funded by the European Commission. It is based in the National Library of the Netherlands, the Koninklijke Bibliotheek. Over 180 heritage and knowledge organisations and IT experts across Europe support Europeana regarding technical and usability issues. Europeana builds on the experience of The European Library, which is a service of the Conference of European National Librarians.

The Europeana website provides efficient tools for searching, FAQ’s, Help’s, a ThoughtLab, a Blog, Newsletters and a personal space My Europeana to save your favourite items and searches, and to add tags. The content is available in most eurpean languages.

An associated project to Europeana is the Public Domain Calculator.

Polaroid Z340 Instant Digital Camera

Since the launch of the Polaroid Land Camera in 1948, the first instant camera, people around the world have enjoyed the magic of Polaroid instant photography. Today Polaroid announced the Z340 Instant Digital Camera,  a full-function 14.0 megapixel digital camera with an integrated ZINK® printer. The Polaroid Z340 camera delivers the same instant experience that is synonymous with the Polaroid brand: a simple, quick and easy way to capture, print, share and create with snapshots from our lives.

The Z340 camera produces vibrant photos with the patented ZINK Paper®, an advanced composite material with cyan, yellow, and magenta dye crystals embedded inside. Before printing, the embedded dye crystals are clear, so the ZINK Paper looks like regular white photo paper.

The Polaroid Z340 camera is available for $299.99 US$. The price for thirty sheets of Polaroid ZINK 3×4” Paper is 19.99 US$.

CBR versus VBR in video encoding

When referring to codecs, CBR (constant bitrate) encoding means that the rate at which a codec’s output data should be consumed is constant. As opposed to constant bitrate, VBR (variable bitrate) vary the amount of output data per time segment. VBR allows you to set a maximum and minimum bitrate. The advantages of VBR are that it produces a better quality-to-space ratio compared to a CBR file of the same data. The bits available are used more flexibly to encode the sound or video data more accurately, with fewer bits used in less demanding passages and more bits used in difficult-to-encode passages.

The disadvantages are that it takes more time to encode, as the process is more complex. VBR may  pose problems when streaming over a  web connection since it is the maximum bit rate that matters, not the average.

The generally accepted best practice is to use CBR when producing for streaming delivery, and VBR when producing for progressive download.

The most common container for H264 encoded videos is specified by MPEG-4 Part 14 (standard ISO 14496-14) and has the file extension mp4. This format, often called MP4 container,  is based on the quicktime format mov. Audio-only MPEG-4 files have a m4a extension, or m4p when they are encrypted.

Apple introduced the extension m4v for it’s iTunes applications. It’s very close to .mp4, some differences are the optional Apple’s DRM copyright protection, and the treatment of AC3 (Dolby Digital) audio which is not standardized for MP4 container

The following command line tools are available to create and modify MP4 files by combining (multiplexing) previously encoded video or audio tracks, as well as subtitles, chapter information and meta data.

• AtomicParsley : lightweight program for reading, parsing and setting metadata into MPEG-4 files
• MP4Creator : tool from Cisco’s mpeg4ip suite that combines video, audio, text and other media to create MPEG-4 streams.

GUI’s for both programs are also available.

More informations about the MPEG-4 containers are listed hereafter :

• Dooms9′s Forum : MP4 FAQ
• Wikipedia : Comparison of container formats

QTIndexSwapper 2 (to move MOOV atom)

When a streaming mp4 H264 video file won’t play immediately, the reason could be a quicktime (QT) Index problem. This index is called MOOV atom. The moov atom, also referred to as the movie atom, defines the timescale, duration, display characteristics of the movie, as well as subatoms containing information for each track in the movie.

Often the moov atom is located at the end of the video file and the player needs to load the entire file to read this information. The solution is simple: Move the moov atom from the end of the file to the beginning. Renaun Erickson, Developer Evangelist for Adobe Systems Inc., created a simple tool called QTIndexSwapper 2 to do this job. This AIR application can be downloaded from his blog. Another tool to move the moov atom is MP4 FastStart.

More informations about atoms in mp4 files are availabale at the following links :

• Atomic Parsley : MPEG-4 files
• Adobe Devnet : Understanding the MPEG-4 movie atom

CABAC : stands for Context Adaptive Binary Arithmetic Coding. Improves encoding efficiency at the expense of playback/decoding efficiency. The default option is on, unless the encoded video is to be played back on devices with limited decoding power (for example iPod). CABAC is only supported by the main and higher profiles.

Trellis : Trellis is only available with CABAC on. It improves quality, while maintaining a small file size but it will increase conversion time slightly. The default value is on.

Encoding mode :

• Single Pass – Bitrate: encodes the video once  with a set constant bitrate for each frame
• Single Pass – Quantizer: encodes the video with a set quantizer (higher quantizer => lower quality) for each frame. The default value is 26, the maximum value  is 51.
• Single Pass – Quality: encodes the video with a set quality rating for each frame
• Two Pass:  encodes the video twice (once to determine it’s properties, another to ensure the selected output file size is reached with maximum efficiency). This is the most common setting.
• Multi Pass: Same as Two Pass except for extra encoding passes to ensure even better quality/accurate file size. During multipass encoding, the video results of the first pass are saved into a log file. In a second step the encoding is done based on the logfile data.

Bit Rate : the average bitrate varies between 0 and 5000 Kbits/s; the default values are 800 Kbits/s for low quality, 1000 Kbit/s for medium quality and 1200 Kbits/s for high quality.

• Keyframe Boost  : High values give better visual quality but also bigger file sizes. The default value for I-Frames is 40%. Values vary from 0 to 70.
• B-Frame reduction : these frames are responsible for the interpretation of motion in the video. This setting determines the reduction of quality in B-frames in favor of P-frames (predicted picture). The default vallue is 30%, the range varies from 0 to 60%. For cartoons higher values are recommended.
• Bitrate variability : This attribute indicates in how far the bitrate is allowed to vary in relation to what is set as target bitrate. A variable bitrate tells the encoder to vary bitrate as needed, based on the information in the frames. The default value is 60%, the range varies from 0 to 100%.

Quantization limits : these values are only used when the Single Pass – Quantizer encoding mode is selected.

• Min QP : Values vary from 0 to 50, the default value is 10.
• Max QP : Values vary from 0 to 51, the default value is 51
• Max QP step : Values vary from 0 to 50, the default value is 4.

Scene cuts : this option sets how H264 determines when a scene change has occurred and hence when a key frame is needed.

• Scene cut threshold : The default value is 40. A higher value will allow H264 to be less sensitive to scene changes. A lower value is recommended for dark videos.
• Min IDR frame interval : IDR means Instantaneous Decode Refresh, a parameter to indicate the amount of frames in between before the encoder can detect a new scene change. Setting this to high will result in not detecting enough scene changes. Setting it too low results in an unnecessary high bitrate. The range varies from 0 to 100.000, the default value is 25.
• Max IDR frame interval : Setting this too low results in too many keyframes and as such wasting bitrate for nothing. The range varies from 0 to 100.000, the default value is 250.

Partitions : During the encoding process, the encoder will break down the video into so-called Macroblocks. Then it will search for similar blocks in order to discard redundant data. The macroblocks can be subdivided into 16×8, 8×16, 8×8, 4×8, 8×4, and 4×4 partitions. The partition searches increase accuracy and compression efficiency. As a general rule, the more search types are performed, the better and stronger the compression will be while maintaining a high quality output.

• 8×8 transform : the 8×8 Adaptive DCT transform is a very powerful compression technique but it is not compatible with every device. It makes the video High Profile AVC.
• 8×8, 8×16 and 16×8 P-Frame search : This settings enables the 8×8 partitions on P-Frames and thus improves the visual quality of these frames.
• 8×8, 8×16 and 16×8 B-Frame search : This settings enables the 8×8 partitions on B-Frames and thus improves the visual quality of these frames.
• 4×4, 4×8 and 8×4 P-Frame search : This settings enables the 4×4 partitions on P-Frames, but usually the quality improvement will be negligible. Therefore this option is not worth the additional encoding time and thus can safely be turned off.
• 8×8 intra search : This settings enables the 8×8 partitions on I-Frames and thus improves the visual quality of these frames, but it requires the 8×8 Adaptive DCT Transform.
• 4×4 intra search : This settings enables the 4×4 partitions on I-Frames and thus improves the visual quality of these frames.

B-Frames :

• Use as a reference : alows a B-Frame to reference another B-Frame to provide better quality. Only useful when using more than 2 consecutive B-Frames.
• Adaptive : Turns on adaptive B-frames, which allows H264 to determine the number of B-frames to use. The default value is on. This option is only available when at least 1 B-frame has been set.
• Bidirectional ME :  allows predictions based on motion both before and after the B-frames. Default value is on.
• Weighted bipredictional :  allows B-Frames to be predicted more heavily from P-Frames which results in improved accuracy and therefore a more efficient encoding. Default value is on. This option is only available when at least 1 B-frame has been set.
• Direct B-Frame mode : temporal or spatial : The default value is temporal. The spatial mode handles better animated content.
• Max consecutive : the number of consecutive B-Frames. The values vary from 0 to 5, the default value is 3.
• Bias : Sets how much bias H264 should give the usage of B-frames (higher means more use of B-frames). Setting this to 100 is the equivalent of not selecting the “Adaptive” option.The default value is 0, possible values vary from -100 to +100.

Motion estimation :

• Partition decision : This controls the precision with which the motion in the video is estimated. Values range from 1 to 6. The default value is 5. A setting of 6 is even better but it strongly increases the amount of time needed for the conversion.
• Method : The better the method, the more efficient compression and high quality output. Hexagonal Search is the default setting. Uneven Multi-hexagon is meant for powerful computers, while Exhaustive search works only on super computers.
• Range : this field is disabled when you select Hexagonal Search. It only works with the powerful methods and it specifies the motion search in the pixels. The more pixels are examined, the more processor power is needed, but the better the outcome. The values vary from 0 to 64, the default value is 16.
• Max Ref Frames : This value indicates how many previous frames can be referenced by a P-frame or B-frame. The higher this value, the better the quality at the expense of speed. The values vary from 0 to 16, the default value is 0.
• Mixed references : offers the codec greater freedom to make references on a smaller scale. This option is only available when the Max Ref Frames value is greater than 1.
• Chroma ME : uses the color information in the video to estimate motions, which increases the visual quality. It is recommended to set this option on.

Misc. options :

• Threads : This sets the number of CPU threads to use in encoding. Default value is 1.
• Noise reduction : this setting depends if there is noise in the video images or not. Videos with noise appear grainyNoise Reduction filters out that noise and the more noise you have, the higher you need to set the value. Varies from 0 to 65535. Default value is 0.
• Deblocking filter : A deblocking filter is a video filter applied to blocks in decoded video to improve visual quality and prediction performance by smoothing the sharp edges which can form between macroblocks when block coding techniques are used. The strength (values from -6 to +6) and threshold (values from -6 to +6) of the filter are set. The default values are 0 and 0.

The H264 specifications define a number of different profiles specifying which compression features of H.264 are allowed or forbidden. In addition to the profiles, the H264 specifications also define a number of levels  putting further restrictions on other properties of the video. These restrictions include the maximum resolution, the maximum bitrate, the maximum framerate. The common notation for Profiles and Levels is “Profile@Level”, for example Main@3.1. There is no way to directly encode a video to a specific level and/or profile,  you must choose the encoder settings accordingly. Presets may be helpful to define the correct settings.

The most common profiles for webstreaming are baseline (BP) and main (MP). Some differences in the features for these profiles are shown hereafter :

The next table shows the maximum values for some common levels :

Further informations about H264 are available at the following websites :

• Miracle Tutorials : Converting video to streaming MP4 for S3 Amazon with AVS Video Converter, by Rudolf Boogerman
• AVS4YOU : H.264 Advanced Settings
• Streaminglearningcenter : Producing H264 Video, by Jan Ozer
• avidemux : H264 encoding guide

MPEG-4 Visual should not be confused with MPEG-4 Part 10 which is commonly referred to as H.264 or AVC (Advanced Video Coding), and was jointly developed by ITU-T and MPEG.

AVC is currently one of the most commonly used formats for the recording, compression, and distribution of high definition video.

synth-ethic

Bio:Fiction is the world’s first synthetic biology film festival. The first and original festival took place at the Museum of Natural History in Vienna, Austria, from 13-14th of May 2011. Since then Bio:Fiction is officially on tour around the world. The festival provided information and dialogue about synthetic biology in an attractive, factual and entertaining way.

Synthetic biology aims at applying engineering principles to biology. The DNA of an organism is no longer manipulated, but programmed on a computer and built up from scratch.

The Festival marked also the beginning of the synbio art exhibition Synth-ethics in the Museum, that presented biotech art objects related to synthetic biology. The exhibition featured 10 artist and lasted from May 14th to June 26th, 2011.

The exhibition was produced by Biofaction KG and is part of the Cinema and Synthetic Biology project, funded by GEN-AU ELSA.

Strandbeest "Animaris Ordis Parvus" Assembly Kit

Theo Jansen, born 14 March 1948, is a Dutch artist and kinetic sculptor. Since 1990 he builds large works, called strandbeests, which resemble skeletons of animals, that are able to walk using wind power on the beaches of the Netherlands. Not pollen or seeds but plastic yellow tubes are used as the basic material of this new creatures. Eventually he wants to put these animals out in herds on the beaches, so they will live their own lives.

Some beach animals  have a stomach consisting of recycled plastic bottles containing air, that can be pumped up to a high pressure by the wind.  Others are able to detect once they have entered water and walk away from it, and one species will even anchor itself to the earth if it senses a storm approaching.

The artworks of Theo Jansen have been presented on numerous websites, TV shows, videos, books, conferences and exhibitions. The movie Strandbeesten, directed by Alexander Schlichter (2008), was presented at the Bio:Fiction festival in 2011.

An assembly kit of a miniature version of the strandbeest Animaris Ordis Parvus is available at the website of the artist. It is produced by Gakken Education Publishing Co. Ltd. Japan.  After assembling, the mini strandbeest walks on the wind, by hand or by blowing against the propeller. Another strandbeest, the mini Rhinocerus, has been published by the same company in Japan.