dBpoweramp DSP Effects

DSP (or Digital Signal Processing) Effects fall into two main categories:

  • Manipulate audio or video data, such as Resize,
  • Perform an action, such as Preserve Source Attributes.

Effects are processed in the order they appear.

DSP Effects

Aspect Ratio change ratio to fit display,
Audio Bitrate set the bitrate to be used for audio encoding
Audio Channel Count increase or decrease channels,
Audio Mute removes all audio,
Audio Volume Normalize adjust volume to match loudness across videos,
Audio Resample audio frequency adjustment,
Brightness & Contrast adjust these values,
Canvas Size change canvas size (image is not resized),
Custom specify custom encoding command line value(s),
Crop takes part an area of the video (X,Y,Width, Height) and encodes the new video using just that part,
Cut encodes a part of the source video, from a set start point and length,
Deinterlace combine interlaced video
Delete Source File remove 'Converted From' file after conversion,
Denoiser removes noise,
Fade audio / video in or out over designated period, note cannot be used with effects which change the length, such as cut,
Flip vertical or horizontal,
Frame Rate sets frames per second
Hue and Saturation changes overall color appearance
Loop repeats the source video a number of times,
Multi-CPU Force CPU resources encoding will use,
Pixel Format chooses the pixel format to be used by the encoder, note not all encoders support all pixel formats,
Play Sound After Conversion plays a notification sound after all videos have been processed,
Preserve Source Attributes preserve date & time, etc,
Reverse invert the video so plays backwards,
Rotate rotates whole video a set angle,
Scale sets resolution of image,
     Sharpen & Blur sharpens or blurs image,
Stream Selection choose if Video / Audio / Subtitles are preserved, or specify which stream to use
Speed Adjust speed up, or slow down video,
     Trim remove a set amount from the beginning or end of video,
     Watermark embeds a watermark on images,

Aspect Ratio

Changes the aspect ratio to match your playback screen, if the ratio is close to the existing, the pixels will be stretched, otherwise black bands are added to sides or top and bottom.


Audio Channel Count


Forces an audio channel count, principally to down-mix 5.1 to two channels.


Audio Volume Normalize


There are 3 different ways of adjusting the volume of audio in a video:

  • EBU R128: a newer standard of ReplayGain, the average loudness is calculated and the volume is adjusted. This method is the recommended method of volume normalization.

  • Adaptive: the best way to describe adaptive, is like having your hand on the volume knob, constantly adjusting it up and down (a window is used to detect loudness) to compensate for quiet parts.

  • Fixed Amplification: Amplifies the audio by a fixed amount, +6 dB is x2, where -6 dB is divide by 2, be careful not to clip audio (go over the maximum).


Audio Resample

Alters the frequency of audio, typically audio is resampled from a higher frequency to a lower frequency for compatibility reasons (video player which cannot play higher frequencies).


Brightness & Contrast

Changes the brightness or contrast of the image, the default values (0 for brightness and 1 for contrast) are base values which do not change the image.


Canvas Size


Sets the canvas size without resizing the image, the original image can be positioned on this new black canvas.


Custom


Enables a custom command to be added to the ffmpeg encoder. For example, setting custom to:

-t 0:0:30

would limit the encoding to 30 seconds only, note the space before -. Custom is applied in addition to any other settings specified (codec and DSP).


Deinterlace

Combines interlaced frames into a non-interlaced video, these parameters can be changed:

Mode: chooses the interlacing mode,
Parity: picture field parity for first frame,
Deinterlace: which frames to deinterlace.


Delete Source File

Allows the source file (file converting from) to be removed after a successful conversion (when converting a batch of files, deletions occur after each file is converted), It is worth testing the converted files using a small number of files before using this effect. Additionally files can be recycled, and empty folders left behind after conversion removed.


Denoiser


Noise can be removed from the video during conversion, there are three different noise removal methods, test each one to find the most suitable for your needs.

  • High Precision 3D: accepts the strength of Luma, Chroma and Temporal

  • Spatial Denoiser: has a single parameter which specifies the strength

  • Wavelet: Specify a threshold, a higher value filters more. Method sets how to apply the filter, Hard zero's all values under threshold, soft reduces values above threshold, and Garrote nullifies the coefficient (is half way between Hard and Soft). Steps specifies the number of times the picture is decomposed. Planes set which planes to process, by default all are. Strength chooses the partial of full denoising, 85% is the default.


Frame Rate


Sets the frames per second for the encoding, if the source is interpolated then use a De-interpolate DSP before this one.


Hue and Saturation


The Hue is the color tone, it can be adjusted to correct for artificial lighting conditions. Saturation adjusts the color intensity.


Multi-CPU Force

Specify the default number of simultaneous encoders (default is 2) and the core count per encoder. Specifying one encoder and 1 core on a dual core machine would allow the machine to function as normal for other tasks whilst encoding.


Preserve Source Attributes

It is possible to copy attributes from the 'Converted From' file, to the 'Converted To' file. Creation Date, Last Accessed, Modified Date and File Attributes (such as read only) are preserved.


Scale

Scale has three offerings: Scale Maximum, Scale Absolute and Scale Percentage. With scale absolute the image is always scaled exactly to the values specified. Scale Maximum will scale down an image to match the values entered, but not scale a lower resolution image up. Finally Scale Percentage scales each image a fixed percentage.


     Sharpen & Blur

The image can be sharpened, or blurred. A higher sharpen value sharpens the image more, test on a sub-set of files before converting.


     Watermark

A PNG image can be used as a watermark, the transparency layer can be used to with the PNG image.