This comes from the proper longhand designation being vertical resolution, followed by the interlaced/progressive notation, and then the frame rate.
#1920X1080 JUST CAUSE 4 IMAGE FULL#
What is seen onscreen is two of these fields, "interlaced" together, to produce a single full frame. The first field (the odd field) contains visible scan lines 21-263 and the second field (the even field) contains visible scan lines 283–525 (though lines 263 and 283 are half-lines). Working with 24p material via video equipment working at NTSC frame rates has many of the same attributes as the 24 frame/s workflow, but is more complicated by the NTSC-rate practice of using telecine pull-down rather than the PAL practice of transferring 24 frame/s material at 25 frame/s.Īt 525 lines analog NTSC video rates (30000/1001 frames per second) a full "interlaced" frame, unlike a progressive frame, is nearly 1/30th of a second and is composed of two separate "fields," each field nearly 1/60 second. NTSC video Conversion of 24p to NTSC-based frame/field rates Again, once the non-linear editor has this information, editing can be performed entirely in terms of 24 frame/s timecode, and the Keykode information preserved for either film cutting or digital intermediate post-production of scanned film images.īecause sound is recorded separately from moving pictures in 24p projects, there are no problems regarding synchronization or audio pitch: the audio material is simply ingested separately from the moving picture material at its natural rate, and synchronized within the non-linear editor.Ģ4p vs. The original film Keykode and 24 frame/s audio timecode can be then be reconciled with the 25 frame/s telecine timecode by the generation of a telecine log file containing this information. Once in the non-linear editing system, the editing system, knowing that the material actually originated 24 frame/s rather than at 25 frame/s, will replay it at the correct speed. The resulting 25 frame/s video can then be transferred into a non-linear editing system at 25 frame/s, maintaining the 1:1 frame correspondence between film frames and video frames. The process of transferring 24 frame/s video at 25 frame/s rates is also the most common method for ingesting 24p film rushes into a non-linear editor. The larger differences between the 30p and 25i framerates will cause less noticeable motion artifacts upon conversion. NTSC to PAL conversion also tends to blur each film frame into the next, and so is seen as a sub-optimal way to view film footage.ģ0p can be preferable over 24p since performing a standards conversion to 25i PAL has fewer technical complexities – any NTSC–PAL converter will do. This was the common result when programs were shot on film or had film portions, edited on NTSC, and then shown in PAL countries (mostly music videos). Thus the viewer would see motion stutter twice per second. If 24p footage cannot be sped up (for example if it were coming through a live NTSC or HD feed), it instead can be converted in a pattern where most frames were held on screen for two fields, but every half second a frame would be held for three fields. Sometimes the audio is pitch shifted to restore the original pitch. As for audio, the ≈4.1% increase in speed raises the pitch by 0.707 of a semitone, which again typically is not noticed. This method incurs no motion artifacts other than the slightly increased speed, which is typically not noticeable. Each 24p frame will take the place of two 50i fields.
The most popular method is to speed up the material by 1/24 (≈4.1%). Main article: Telecine Converting 24p to PAL Ģ4p material can be converted to the PAL format with the same methods used to convert film to PAL. Of these two, the PAL route is the simpler, but each has its own complications. There are two common workflows for processing 24p material using video equipment, one using PAL frame rates, and the other using NTSC frame rates. 24p material requires care when it is processed using equipment designed for standard video frame rates. When working entirely within the digital non-linear domain, 24p material is more easily handled than material of higher frame rates. Some vendors advertise 24p products as a cheaper alternative to film acquisition.
Today, 24p formats are being increasingly used for aesthetic reasons in image acquisition, delivering film-like motion characteristics. Originally, 24p was used in the non-linear editing of film-originated material. In video technology, 24p refers to a video format that operates at 24 frames per second (typically, 23.976 frame/s when using equipment based on NTSC frame rates, but now 24.000 in many cases) frame rate with progressive scanning (not interlaced).
0 kommentar(er)
