Ffmpeg.exe-I f:/karaoke-AB 56-ar 22050-B 500-R 15-s 320x240 F:/11.flv
FFmpeg-I f:/01.wmv-AB 56-ar 22050-B 500-R 15-s 320x240 F:/test. FLV
Use the-SS parameter (time_off set the Start Time Offset) to start the conversion task from a specified time point. For example:
Capture the thumbnail while converting the file format:
FFmpeg-I "test. Avi"-y-F image2-SS 8-T 0.001-s 350x240 'test.jpg'
Capture existing FLV images:
FFmpeg-I "test. FLV"-y-F image2-SS 8-T 0.001-s 350x240 'test.jpg'
-SS followed by time in seconds
FFmpeg conversion command
FFmpeg-y-I test. MPEG-bitexact-vcodec h263-B 128-R 15-s 176x144-acodec AAC-AC 2-ar 22500
-AB 24-F 3GP test.3gp
Or
FFmpeg-y-I test. MPEG-Ac 1-acodec amr_nb-ar 8000-s 176x144-B 128-R 15 test.3gp
Description of FFMPEG parameter settings
-Bitexact uses standard Bit Rate
-Use Xvid to compress vcodec Xvid
-S 320x240 specify resolution
-R 29.97 attention rate (it can be changed to confirm that non-standard attention rate will cause audio and video not to be synchronized, so it can only be set to 15 or 29.97)
Select one of the image parts.
-B <bit rate> specifies the compression bit rate. It seems that FFmpeg is an automatic VBR. If it is specified, it is probably an average bit rate, for example, 768,1500.
Is existing in the default project.
-Qscale <value> A <value> quality-based VBR. The value ranges from 0.01 to 255. The smaller the value, the better the quality.
-Qmin <value> sets the minimum quality, which is shared with-Qmax (sets the maximum quality), for example,-qmin 10-Qmax 31.
-Sameq uses the same quality as the source.
Sound part
-Acodec AAC: Set the sound encoding.
-AC <value> specifies the number of audio channels. The value 1 indicates the single channel, and the value 2 indicates the stereo mode. You can use 1 (save half of the capacity) to convert the single channel.
DVDRip of can use 2
-Ar <sampling rate> sets the sound sampling rate. psp only recognizes 24000.
-AB <bit rate> sets the sound bit rate. When the front-ac is set to stereo, it must be set to half the bit rate. For example, if it is set to 192kbps, it is set to 96.
The default bit rate is small. We recommend that you set it to 160 kbps (80) or above if you want to hear high-quality sound.
-Vol <percentage> sets the volume. For some DVDRip, the AC3 track volume is very small. You can use this method to increase the volume during conversion. For example, 200 is twice the original volume.
In this way, if you want to get a high-definition, low-capacity MP4 video, you 'd better not use a fixed bit rate, but use the VBR parameter to let the program go.
Judgment, and the sound quality parameter can be improved a little on the basis of the original, it sounds much more comfortable, not too big (depending on the situation adjustment)
Example: FFmpeg-y-I "1.avi"-title" test "-vcodec XviD-s 368x208-r 29.97-B 1500-acodec AAC-AC 2-ar 24000-AB 128-Vol 200-f psp-muxvisual 768 "1. ***"
Explanation: The preceding commands can be entered in the doscommand line or created to run in a batch file. However, the premise is that it should be executed in the directory where FFmpeg is located (the cores subdirectory under the directory where conversion is located ).
Parameters:
-Y (overwrite the output file, that is, if the 1. *** file already exists, it will be overwritten without prompt)
-I "1.avi" (the input file is a 1. AVI file in the same directory as FFMPEG. You can add the path and change the name)
-Title "test" (the title of the video displayed in PSP)
-Vcodec Xvid (videos are compressed using Xvid encoding and cannot be changed)
-S 368x208 (the output resolution is 368x208. Note that the source of the video must be or it will be deformed)
-R 29.97 (the number of frames. This is generally used)
-B 1500 (for video data traffic, use the-B XXXX command to use a fixed bit rate. The number can be changed as needed, and the value above 1500 does not work. Dynamic bit rates can also be used, for example: -The quality of qscale 4 and-qscale 6 is 6)
-Acodec aac (AAC for Audio Encoding)
-AC 2 (number of audio channels: 1 or 2)
-Ar 24000 (sound sampling frequency, as if PSP only supports 24000Hz)
-AB 128 (audio data traffic, usually 32, 64, 96, 128)
-Vol 200 (200% volume, change by yourself)
-F psp (dedicated output PSP format)
-Muxvb 768 (it seems to be the bit rate recognized by PSP machines. Generally, we select 384, 512, and 768. if I change it to 1500, PSP will say the file is damaged)
"1. ***" (output file name, you can also add a path to change the file name)
If the machine is strong, several more files can be opened for parallel processing.
E:/ffmpeg.exe-I:/1.wmv-B 360-R 25-s 320x240-HQ-deinterlace-AB 56-ar 22050-Ac 1 D:/2.flv
