Add a return_array parameter #294

musicalgestures/__init__.py

@@ -25,6 +25,9 @@ class MgVideo(MgAudio):
     def __init__(
             self,
             filename,
+            array=None,
+            fps=None,
+            path=None,
             # Video parameters
             filtertype='Regular',
             thresh=0.05,
@@ -50,6 +53,9 @@ def __init__(
 
         Args:
             filename (str): Path to the video file.
+            array (np.ndarray, optional): Generates an MgVideo object from a video array. Defauts to None.
+            fps (float, optional): The frequency at which consecutive images from the video array are captured or displayed. Defauts to None.
+            path (str, optional): Path to save the output video file generated from a video array. Defaults to None.
             filtertype (str, optional): The `filtertype` parameter for the `motion()` method. `Regular` turns all values below `thresh` to 0. `Binary` turns all values below `thresh` to 0, above `thresh` to 1. `Blob` removes individual pixels with erosion method. Defaults to 'Regular'.
             thresh (float, optional): The `thresh` parameter for the `motion()` method. Eliminates pixel values less than given threshold. A number in the range of 0 to 1. Defaults to 0.05.
             starttime (int or float, optional): Trims the video from this start time (s). Defaults to 0.
@@ -64,13 +70,16 @@ def __init__(
             crop (str, optional): If 'manual', opens a window displaying the first frame of the input video file, where the user can draw a rectangle to which cropping is applied. If 'auto' the cropping function attempts to determine the area of significant motion and applies the cropping to that area. Defaults to 'None'. 
             keep_all (bool, optional): If True, preserves an output video file after each used preprocessing stage. Defaults to False.
             returned_by_process (bool, optional): This parameter is only for internal use, do not use it. Defaults to False.
-
+            
             sr (int, optional): Sampling rate of the audio file. Defaults to 22050.
             n_fft (int, optional): Length of the FFT window. Defaults to 2048.
             hop_length (int, optional): Number of samples between successive frames. Defaults to 512.
         """
 
         self.filename = filename
+        self.array = array
+        self.fps = fps
+        self.path = path
         # Name of file without extension (only-filename)
         self.of = os.path.splitext(self.filename)[0]
         self.fex = os.path.splitext(self.filename)[1]
@@ -94,9 +103,16 @@ def __init__(
         self.sr = sr
         self.n_fft = n_fft
         self.hop_length = hop_length 
-        
+
         self.test_input()
-        self.get_video()
+
+        if all(arg is not None for arg in [self.array, self.fps]):
+            if self.path is None:
+                self.path = os.getcwd()
+            self.from_numpy(self.array, self.fps, self.path)
+        else:
+            self.get_video()
+
         self.info()
         self.flow = Flow(self, self.filename, self.color, self.has_audio)
 
@@ -124,7 +140,7 @@ def __init__(
 
     def test_input(self):
         """Gives feedback to user if initialization from input went wrong."""
-        mg_input_test(self.filename, self.filtertype, self.thresh, self.starttime, self.endtime, self.blur, self.skip, self.frames)
+        mg_input_test(self.filename, self.array, self.fps, self.filtertype, self.thresh, self.starttime, self.endtime, self.blur, self.skip, self.frames)
 
     def info(self, type='video'):
         """Retrieves the information related to video, audio and format."""
@@ -192,6 +208,8 @@ def average(self, filename=None, normalize=True, target_name=None, overwrite=Fal
     ##################################################
 
     def numpy(self):
+        import subprocess
+
         "Pipe all video frames from FFmpeg to numpy array"
         # Define ffmpeg command and pipe it
         cmd = ['ffmpeg', '-y', '-i', self.filename]
@@ -205,7 +223,27 @@ def numpy(self):
         except ValueError:
             pass
 
-        return array
+        return array, self.fps
+
+    def from_numpy(self, array, fps, output_path):
+        import subprocess
+
+        # enforce avi
+        of, fex = os.path.splitext(self.filename)
+        self.filename = of + '.avi'
+        output_path = os.path.join(output_path, self.filename)
+        process = None
+        for frame in array:
+            if process is None:
+                cmd =['ffmpeg', '-y', '-s', '%dx%d' % (frame.shape[1], frame.shape[0]), '-r', str(fps),
+                    '-c:v', 'rawvideo', '-f', 'rawvideo', '-pix_fmt', 'bgr24', '-i', '-', output_path]
+                process = subprocess.Popen(cmd, stdin=subprocess.PIPE)
+            process.stdin.write(frame.tostring())
+        process.stdin.close()
+        process.wait()
+
+        # Save generated musicalgestures video as the video of the parent MgVideo
+        return self.get_video()
 
 
 class Examples:

musicalgestures/_grid.py

@@ -1,10 +1,9 @@
-import os
+import os, subprocess
 import cv2
-import musicalgestures
-import matplotlib.pyplot as plt
+import numpy as np
 from musicalgestures._utils import MgImage, generate_outfilename, ffmpeg_cmd, get_length
 
-def mg_grid(self, height=300, rows=3, cols=3, padding=0, margin=0, target_name=None, overwrite=False):
+def mg_grid(self, height=300, rows=3, cols=3, padding=0, margin=0, target_name=None, overwrite=False, return_array=False):
     """
     Generates frame strip video preview using ffmpeg.
 
@@ -16,6 +15,7 @@ def mg_grid(self, height=300, rows=3, cols=3, padding=0, margin=0, target_name=N
         margin (int, optional): Margin size for the grid. Defaults to 0.
         target_name ([type], optional): Target output name for the grid image. Defaults to None.
         overwrite (bool, optional): Whether to allow overwriting existing files or to automatically increment target filenames to avoid overwriting. Defaults to False.
+        return_array (bool, optional): Whether to return an array of not. If set to False the function writes the grid image to disk. Defaults to False.
 
     Returns:
         MgImage: An MgImage object referring to the internal grid image.
@@ -36,13 +36,24 @@ def mg_grid(self, height=300, rows=3, cols=3, padding=0, margin=0, target_name=N
     nth_frame = int(nb_frames / (rows*cols))
 
     # Define the grid specifications
-    grid = f"select=not(mod(n\,{nth_frame})),scale=-1:{height},tile={cols}x{rows}:padding={padding}:margin={margin}"
-
-    # Declare the ffmpeg command
-    cmd = ['ffmpeg', '-i', self.filename, '-y', '-frames', '1', '-q:v', '0', '-vf', grid, target_name]
-    ffmpeg_cmd(cmd, get_length(self.filename), pb_prefix='Rendering video frame grid:')
-
-    # Initialize the MgImage object
-    img = MgImage(target_name)
-
-    return img
+    width = int((float(self.width) / self.height) * height)
+    grid = f"select=not(mod(n\,{nth_frame})),scale={width}:{height},tile={cols}x{rows}:padding={padding}:margin={margin}"
+
+    # Declare the ffmpeg commands
+    if return_array:
+        cmd = ['ffmpeg', '-y', '-i', self.filename, '-frames', '1', '-q:v', '0', '-vf', grid]
+        process = ffmpeg_cmd(cmd, get_length(self.filename), pb_prefix='Rendering video frame grid:', pipe='load')
+
+        if self.color:
+            array = np.frombuffer(process.stdout, dtype=np.uint8).reshape([-1, height*rows, int(width*cols), 3])
+        else:
+            array = np.frombuffer(process.stdout, dtype=np.uint8).reshape(-1, height*rows, int(width*cols))
+
+        return array
+    else:
+        cmd = ['ffmpeg', '-i', self.filename, '-y', '-frames', '1', '-q:v', '0', '-vf', grid, target_name]
+        ffmpeg_cmd(cmd, get_length(self.filename), pb_prefix='Rendering video frame grid:')
+        # Initialize the MgImage object
+        img = MgImage(target_name)
+
+        return img

musicalgestures/_input_test.py

@@ -15,12 +15,14 @@ def __init__(self, message):
         self.message = message
 
 
-def mg_input_test(filename, filtertype, thresh, starttime, endtime, blur, skip, frames):
+def mg_input_test(filename, array, fps, filtertype, thresh, starttime, endtime, blur, skip, frames):
     """
     Gives feedback to user if initialization from input went wrong.
 
     Args:
         filename (str): Path to the input video file.
+        array (np.ndarray, optional): Generates an MgVideo object from a video array. Defauts to None.
+        fps (float, optional): The frequency at which consecutive images from the video array are captured or displayed. Defauts to None.
         filtertype (str): 'Regular' turns all values below `thresh` to 0. 'Binary' turns all values below `thresh` to 0, above `thresh` to 1. 'Blob' removes individual pixels with erosion method.
         thresh (float): A number in the range of 0 to 1. Eliminates pixel values less than given threshold.
         starttime (int/float): Trims the video from this start time (s).
@@ -36,6 +38,11 @@ def mg_input_test(filename, filtertype, thresh, starttime, endtime, blur, skip,
     filenametest = type(filename) == str
 
     if filenametest:
+        if array is not None:
+            if fps is None:
+                msg = 'Please specify frame per second (fps) parameter for generating video from array.'
+                raise InputError(msg)
+
         if filtertype.lower() not in ['regular', 'binary', 'blob']:
             msg = 'Please specify a filter type as str: "Regular", "Binary" or "Blob"'
             raise InputError(msg)

musicalgestures/_utils.py

@@ -977,8 +977,7 @@ def extract_wav(filename, target_name=None, overwrite=False):
         print(f'{filename} is already in .wav container.')
         return filename
 
-    cmds = ' '.join(['ffmpeg', '-loglevel', 'quiet', '-y', '-i', wrap_str(filename), "-acodec",
-                     "pcm_s16le", wrap_str(target_name)])
+    cmds = ' '.join(['ffmpeg', '-loglevel', 'quiet', '-y', '-i', wrap_str(filename), "-acodec", "pcm_s16le", wrap_str(target_name)])
     os.system(cmds)
     return target_name
 
@@ -1407,13 +1406,13 @@ def ffmpeg_cmd(command, total_time, pb_prefix='Progress', print_cmd=False, strea
 
     if pipe == 'read':
         # Define ffmpeg command and read frame by frame
-        command = command + ['-f', 'image2pipe', '-pix_fmt', 'bgr24', '-vcodec', 'rawvideo', '-']
+        command = command + ['-f', 'image2pipe', '-pix_fmt', 'bgr24', '-vcodec', 'rawvideo', '-preset', 'ultrafast', '-']
         process = subprocess.Popen(command, stdout=subprocess.PIPE, bufsize=-1)
         return process
 
     elif pipe == 'load':
         # Define ffmpeg command and load all frames
-        command = command + ['-f', 'image2pipe', '-pix_fmt', 'bgr24', '-vcodec', 'rawvideo', '-']
+        command = command + ['-f', 'image2pipe', '-pix_fmt', 'bgr24', '-vcodec', 'rawvideo', '-preset', 'ultrafast', '-']
         process = subprocess.run(command, stdout=subprocess.PIPE, bufsize=-1)
         return process