Data Frame Transcode 1-0

Data Frame Transcode 1-0

Content Index :

Data Frame Transcode 1-0
Tag : r , By : Raghu
Date : November 28 2020, 11:01 PM

This might help you I'd like to transform some columns of a data frame in [0,1]. , Assuming your variables are not factors, you can simply do:
df[df == 'YES'] <- 1
df[df == 'NO'] <- 0

No Comments Right Now !

Boards Message :
You Must Login Or Sign Up to Add Your Comments .

Share : facebook icon twitter icon

libavcodec, how to transcode video with different frame rates?

Tag : cpp , By : Chris Woods
Date : March 29 2020, 07:55 AM
wish helps you Most simple solution would be to use two threads. First thread would do all the things outlined in your question (decoding, scaling / color-space conversion, coding). Partially transcoded frames would be written to intermediate queue shared with second thread. Maximum length of this queue would be in this particular case (converting from lower to higher bitrate) 1 frame. Second thread would be reading in loop frames from input queue like this:
void FpsConverter::ThreadProc()

DWORD start_time = timeGetTime();
int frame_counter = 0;
while(!shouldFinish()) {
    Frame *frame = NULL;
    DWORD time_begin = timeGetTime();
    DWORD time_end = timeGetTime();
    DWORD next_frame_time = start_time + ++frame_counter * frame_time;
    DWORD time_to_sleep = next_frame_time - time_end;
    if (time_to_sleep > 0) {

using libvlc_video_set_format_callbacks to transcode videos frame by frame

Tag : cpp , By : user152319
Date : March 29 2020, 07:55 AM
should help you out liblv_video_set_format_callbacks second argument is of type libvlc_video_format_cb, which is the following typedef:
typedef unsigned(* libvlc_video_format_cb)(void **opaque, char *chroma, unsigned *width, unsigned *height, unsigned *pitches, unsigned *lines);

Transcode of H.264 to VP8 using libav* has incorrect frame rate

Tag : c , By : xie renhui
Date : March 29 2020, 07:55 AM
like below fixes the issue It appears that your problem is in your transcoding function you need to av_rescale_q between your input format PTS/DTS and output format PTS/DTS.
Don't trust putting arbitrary numbers in either, continue doing what you're doing by getting it from the context and codec.

How to transcode a stream of data using FFMpeg (C#)

Tag : chash , By : Jody Bannon
Date : March 29 2020, 07:55 AM
To fix this issue To solve this, I have spawned a new FFMpeg process. Then I used the pipe command and sent in the data via standard input, and got the output using the standard output. I then converted the output I received to a byte array. The new byte array is the transcoded data. You can write this byte buffer to a memory stream or a file stream, you can do what you like.
        var startInfo = new ProcessStartInfo('path/to/ffmpeg');
        startInfo.RedirectStandardInput = true;
        startInfo.RedirectStandardOutput = true;
        startInfo.UseShellExecute = false;

        var argumentBuilder = new List<string>();
        argumentBuilder.Add("-loglevel panic"); // this makes sure only data is sent to stdout
        argumentBuilder.Add("-i pipe:.mp3"); //this sets the input to stdin

        // the target audio specs are as follows
        argumentBuilder.Add($"-f wav");
        argumentBuilder.Add("-ac 1");
        argumentBuilder.Add($"-ar 44100");
        argumentBuilder.Add("pipe:1"); // this sets the output to stdout

        startInfo.Arguments = String.Join(" ", argumentBuilder.ToArray());

        _ffMpegProcess = new Process();
        _ffMpegProcess.StartInfo = startInfo;

        while (true)
            var bytes = new byte[1024]
            var result = await _ffMpegProcess.StandardOutput.BaseStream.ReadAsync(bytes);

            if (result == 0)
               // no data retrieved
               // do something with the data

Dump last frame of video file using ffmpeg/mencoder/transcode et. al

Tag : ffmpeg , By : Maplye
Date : March 29 2020, 07:55 AM
Related Posts Related QUESTIONS :
  • Slope of time series (xts) object over rolling window
  • Is there an R function for comparing rows in data.frame?
  • Changing linetype and line color with plot_model()
  • Update existing package on CRAN
  • Delete NA data ,but with certain condition in R
  • calculate number and names of similar sounding words from a data frame
  • Reset input fields of dynamically generated widgets through insertUI
  • How to get the coordinates that spits out min/max value from the function in R?
  • running t.test() on multiple columns to output tibble
  • Conditionally replace the values in columns to value in another column using dplyr
  • Add count as label to points in geom_count
  • Temporarily Disable Rprofile
  • Select certain region of column for lm
  • Convert multiple rows into one row depending on unique values in another column
  • Issues installing Plotly Dash for R
  • Is there an R function to retrieve values from a matrix of column names?
  • R;Too slow to overate loops for million vectors
  • How to optimize intersect of rows and columns in a matrix?
  • Format and export the output of Mann-Kendall test in R to excel from Rstudio
  • how to calculate cumsum with depreciation in a grouped dataframe?
  • reshape wide to long based on part of column name
  • How to get a hyperlink for the words in a description in an r dataframe?
  • shinymeta works locally but breaks when published to shinyapps.io
  • Deparse and (un)escape quotes
  • Regression table with clustered standard errors in R jupyter notebook?
  • Disaggregate quarterly data to daily data in R keeping values?
  • How to save output to console and file simultaneously in RStudio server?
  • Why does data.table j have a different environment when directly calling mget() vs calling mget() inside another functio
  • scale_fill_viridis_c color bar on a log scale
  • How to change the lab name corresponding to function in ggplot
  • R, filtering for an element in a list in a dataframe cell
  • Extracting only bottom temperature from 4d NetCDF file
  • How to add/wrap lines of text to .tex with .sh script
  • R - building new variables from sequenced data
  • Sum rows values one after the other
  • Nesting ifelse inside summarytools
  • How best to divide different levels of a factor by one another in dataframe in R?
  • Why does my code run multiple times before I type data into the table? How do I make an action button that creates a tab
  • How to impute missing values not at random?
  • Set the y limits of an added average line of a plotly plot
  • how to calculate a new column after grouping with dplyr
  • Extract data from rows creating new columns using R
  • Create a filled area line plot with plotly
  • When do I need parentheses around an if statement to control the sequence of a formula in R?
  • my graph in ggplot2 contains an "e" character in y-axis
  • Making variables immutable in R
  • R: Difference between the subsequent ranks of a item group by date
  • Match data within multiple time-frames with dplyr
  • Conditional manipulation and extension of rows in data.table also considering previous extensions without for-loop
  • Conditional formula referring to preview row in DF not working
  • Set hoverinfo text in plotly scatterplot
  • Histogram of Sums from Categorical/Binary Data
  • Efficiently find set differences and generate random sample
  • Find closest points from data set B to point in data set A, using lat long in R
  • dplyr join on column A OR column B
  • Replace all string if row starts with (within a column)
  • Is there a possibility to combine position_stack and nudge_x in a stacked bar chart in ggplot2?
  • How can I extract bounding boxes in a row-wise manner using R?
  • How do I easily sum up values in different columns?
  • Reading numeric Date value from CSV file to data.frame in "R"
  • shadow
    Privacy Policy - Terms - Contact Us © scrbit.com