Multimedia english: Difference between revisions
(→Video) |
|||
| (2 intermediate revisions by one other user not shown) | |||
| Line 22: | Line 22: | ||
As long as the codec that was used for the video is installed on the system, the video can be played in Visionaire as well. If a created game (including videos) is provided to other people, you have to make sure, that the videos either use a codec that is already present on a usual system, or that the installer of the game also installs the required codec. | As long as the codec that was used for the video is installed on the system, the video can be played in Visionaire as well. If a created game (including videos) is provided to other people, you have to make sure, that the videos either use a codec that is already present on a usual system, or that the installer of the game also installs the required codec. | ||
The width and height of a video is recommended to be to the power of 2 (2^n, e.g.: 256, 512) or just below such a number. In OpenGL the single frames of a video are displayed as a texture. The size of the texture has to be such a number. For example, if the video has a size of 512x512 then it can be played using a texture of 512x512. But if the video has the dimensions of 560x540 then a texture of 1024x1024 is required. | The width and height of a video is recommended to be to the power of 2 (2^n, e.g.: 256, 512) or just below such a number. In OpenGL the single frames of a video are displayed as a texture. The size of the texture has to be such a number. For example, if the video has a size of 512x512 then it can be played using a texture of 512x512. But if the video has the dimensions of 560x540 then a texture of 1024x1024 is required. Sometimes older graphic cards can only create textures of a size up to 512x512. Therefore bigger videos cannot be displayed correctly on these cards. | ||
Latest revision as of 12:15, 31 December 2006
Graphics
Visionaire supports the following graphic formats: PNG, JPEG, GIF and PCX. The recommended format for Visionaire is PNG.
- PNG (Portable Network Grahpics): This graphic format supports a good lossless compression, 16 million colors and an alpha channel. With the alpha channel it is possible to create half transparent images which can overlap the background with a given opacity. Due to this features PNG is the graphic format of first choice.
- JPEG (Joint Photographic Experts Group): This graphic format supports a good lossy compression and 16 million colors. The compression is especially visible on drawn images. Thus this format should only be used for photorealistic background images where the artefacts (from the compression) don't matter.
- GIF (Graphics Interchange Format): This is a graphic format with a good lossless compression but only supoorts 256 colors. Multiple images can be included as well but this feature is not supported by Visionaire. Visionaire uses Animations for image sequences.
- PCX (PiCture eXchange): This graphic format uses a simple lossless compression and supports up to 16 million colors (the number of colors depends on the format version). This format has a worse compression and no advantages compared to the other formats. Thus it should not be used.
Sound
Currently Visionaire supports the following sound file formats: MP3 and WAV (the goal is to support further formats in the future).
- MP3 (MPEG-1 Audio Layer 3): It provides a very good data compression and should be used especially for background music and bigger music files. It has to be noted that the use of the format requires to purchase a licence, which depends on many factors. We recommend to investigate this concerning the specific application before deciding to use it, so that no license problems arise.
See also www.mp3licensing.com. - WAV: This is a container format for audio data and provides a good sound quality. The format is most appropriate for noises and sounds and speech.
Video
As long as the codec that was used for the video is installed on the system, the video can be played in Visionaire as well. If a created game (including videos) is provided to other people, you have to make sure, that the videos either use a codec that is already present on a usual system, or that the installer of the game also installs the required codec.
The width and height of a video is recommended to be to the power of 2 (2^n, e.g.: 256, 512) or just below such a number. In OpenGL the single frames of a video are displayed as a texture. The size of the texture has to be such a number. For example, if the video has a size of 512x512 then it can be played using a texture of 512x512. But if the video has the dimensions of 560x540 then a texture of 1024x1024 is required. Sometimes older graphic cards can only create textures of a size up to 512x512. Therefore bigger videos cannot be displayed correctly on these cards.