I have a script that modifies position and rotation of some objects as well as individual verticies. For each frame I render PNG and then I insert them to video sequence to render the final video. The problem is that I have 6000 frames and the individual image files are quite large. **Is there a way to append the frames as they are created in the for loop to single video file?** As I understand it I can't keyframe individual verticies and therefore can't create only keyframes in the for loop and render the video afterwards

Here is the code:

```
import bpy
import csv

FILE = 'Data/20200712.csv'
OUTPUT = 'Other/Output/'

#
fp = bpy.context.scene.render.filepath # get existing output path
bpy.context.scene.render.image_settings.file_format = 'PNG' # set output format to .png

arrow = bpy.data.objects['Arrow']
target = bpy.data.objects['Target']

#find which vertex of pyramid is moving
bottom = bpy.data.objects['Cover']
for i, vert in enumerate(bottom.data.vertices):
    if vert.co[2]>0.5:
        ind = i

with open(filename, newline='') as data:
    reader = csv.DictReader(data)
    counter = 0
    for row in reader:
        if row['A'] is not None:
            frame_num = int(row['SampleTime'])

            x = float(row['hB'])            #load value saved as hB

            y = float(row['hA'])            #load value saved as hA

            arrow.rotation_euler = (-y/3, x/3, 0)

            target.location = (row['gestTarget0'], row['gestTarget1'], 0.9)

            bottom.data.vertices[ind].co[0] = x/5
            bottom.data.vertices[ind].co[1] = y/5

            bpy.context.scene.frame_set(frame_num)
            #arrow.keyframe_insert(data_path="location", frame=frame_num)
            arrow.keyframe_insert(data_path='rotation_euler', frame=frame_num)

            target.keyframe_insert(data_path="location", frame=frame_num)

            bpy.context.scene.frame_current = frame_num
            bpy.context.scene.render.filepath = OUTPUT + str(frame_num)
            bpy.ops.render.render(write_still=True) # render still

#        counter += 1
#        
#        if counter>200:
#            break

bpy.context.scene.render.filepath = fp #restore filepath
```

```