Simple python script to stitch images into movie failing with incorrect context

Question

I'm trying to write a simple script that adds png images to the video seqeuence editor, and stitches them into a movie. However, between the blender API and all of the old documentation that's floating around online, I can't seem to get it to work. Here's my code:

import bpy
import os, glob
img_dir = 'my/img/dir'
set movie render settings
resx = 1024
resy = 350
bpy.data.scenes["Scene"].render.resolution_x = resx
bpy.data.scenes["Scene"].render.resolution_y = resy
bpy.data.scenes["Scene"].render.resolution_percentage = 100
scene = bpy.data.scenes[0]
editor = scene.sequence_editor_create()
get image files
image_files = []
for _file in os.listdir(path=img_dir):
    if _file.endswith('.png'):
        image_files.append(_file)
context = bpy.context
add to sequencer
img_strip = [{'name':i} for i in image_files]
frames = len(image_files)
frame_end = frames - 1  # offset for python counting
a = bpy.ops.sequencer.image_strip_add(directory=img_dir, files=img_strip,
    channel=1, frame_start=0, frame_end=frame_end)
strip_name = file[0].get("name")
bpy.data.scenes["Scene"].frame_end = frames
bpy.data.scenes["Scene"].render.image_settings.file_format = 'AVI_JPEG'
bpy.data.scenes["Scene"].render.filepath = out_dir
bpy.ops.render.render( animation=True )

with output:

line 32, in <module>
    channel=1, frame_start=0, frame_end=frame_end)
  File "/usr/share/blender/scripts/modules/bpy/ops.py", line 189, in __call__
    ret = op_call(self.idname_py(), None, kw)
RuntimeError: Operator bpy.ops.sequencer.image_strip_add.poll() failed, context is incorrect

What does this error mean? And how might I go about modifying my code?

Answer 1

Ditch the operator.

Have updated the code from

Importing multiple movie clips inside one directory via script

• look at all images in a path
• glob on "*.png"
• to use pathlib.Path

Adding each image as a strip.

import bpy
from pathlib import Path
glob all movie files from
dir_path = "/home/batfinger/Pictures"
img_dir = Path(dir_path)
glob = "*.png"
frame_duration = 24
files = sorted(list(img_dir.glob(glob)))
get sequence editor
scene = bpy.context.scene
#scene.sequence_editor_clear()
sed = scene.sequence_editor_create()
seq = sed.sequences
add movie strips
for i, fp in enumerate(files):
    ms = seq.new_image(
            name=fp.name,
            filepath=str(fp),
            channel=i + 1,
            frame_start= i * frame_duration + 1 ,
        )
ms.frame_final_duration = frame_duration
# print some details
print("%s ch: %d fs: %3.1f len: %d" %
        (fp.name, i + 1, ms.frame_start, ms.frame_final_duration)
        )

Adding images as sequence to one strip.

import bpy
from pathlib import Path
dir_path = "/home/batfinger/Pictures"
img_dir = Path(dir_path)
glob = "*.png"
frame_duration = 24
files = sorted(list(img_dir.glob(glob)))
get sequence editor
scene = bpy.context.scene
#scene.sequence_editor_clear()
sed = scene.sequence_editor_create()
seq = sed.sequences
duration = len(files)
add image strip using first
fp = files.pop(0)
imstrip = seq.new_image(
    name=fp.name,
    filepath=str(fp),
    frame_start=1,
    channel=1,
    )
add the elements
while files:
    imstrip.elements.append(files.pop(0).name)
imstrip.frame_final_duration = duration
imstrip.update()

Answer 2

As batFINGER suggested, you get this error because you try run a function in a context that is not suitable. If you click on the run/start-button in the text editor, the context of the running code is the TEXT_EDITOR, not the SEQUENCE_EDITOR. Therefore, you would have to switch context.

This can be done as follows (see response of eceathar for the original solution):

area = bpy.context.area
old_type = area.type
area.type = 'SEQUENCE_EDITOR'
call the image_strip_add here and other functions
area.type = old_type

Further reading: poll() failed, context incorrect? - Example: bpy.ops.view3d.background_image_add()