Friends who often use CHS Zero One video series should be familiar with "sample files". In various cases, we also strongly recommend loading sample files during video scanning, and sample files become a must for video restoration. Today let's talk about the role and usage requirements of sample files.
What are sample files?
From the perspective of data recovery in a broad sense, all repairs require sample files, such as databases or videos. It's just that some things that can be predefined are done in the background, such as the system table of the database.
Explained from the perspective of video restoration and repair, it is related to the file structure of the video. First, a video has metadata. These metadata must provide important parameters such as audio encoding, video encoding, and rate. These parameters are not only used in decoding. It is useful at times, and it plays a major role in finding video fragments and reorganizing fragments. Let’s take CHS Zero One Video Recovery Professional Edition as an example to recover recorder MP4. As shown in the figure below, you can see that the program has analyzed these important parameters. In the subsequent process of fragment location and reorganization, it will focus on screening qualified video frames and audio frames. and the moov structure. Of course, you can directly select the automatic identification recorder here, but the value given in the sample file is more accurate. So we can get the following difference between automatic recognition and sample files:
Sample file: exact parameters -> builds exact model -> works great
Automatic recognition: fuzzy parameters (derived from the common parameters of the same kind of cameras that are usually processed)->establish fuzzy models->common models have excellent effects, and some unpopular models have slightly worse effects
Sample file requirements?
- two or three
same camera
The same parameters (video encoding, exposure, etc. parameters in the camera): you can consult the photographer, or check the consecutive file names before and after as a reference.
Files generated by editing software plus: the same editing software, the same version, the same parameters.
- raw code
If the transmission is through communication apps such as QQ and WeChat, it is extremely important to compress the file before transferring, because most communication apps will transcode and compress the original file for the convenience of transmission, and transcoding will lose the original file. encoding features, and the use of compressed packages will protect the integrity of video files!
How to get the sample file when there is no file in the card after formatting?
In this case, as long as the device is on, it can be solved by re-shooting to generate a new file.
Note that before re-shooting, you must make a mirror image, or use a new card to prevent data from being overwritten again. In addition, there is no limit to the scenes to be re-shot, but the length of time must be at least three minutes.