Image sequence to mp4 / h264

[sr9yar]

Hello,
I'm using your library to put an image sequence into mp4/h264 file.
I'd like to use this format to be able to play the video in a web browser.
Basically I used an example here https://github.com/mikeboers/PyAV/blob/master/examples/encode_frames.py

Here is my code:

import os
import numpy as np
import cv2
import av


#
# example
# https://github.com/mikeboers/PyAV/blob/master/examples/encode_frames.py
#

# fps = '29.97'
fps = '23.976'

# size = (640,360)

# libx264
codec = 'h264'
# codec = 'x264'
# codec = 'mpeg4'

bitrate = 8000000
fmt = 'yuv420p'

def get_filename(i):
  s = str(i)
  while len(s) < 4:
	s = '0' + s
  return '/app/rendering/ffd06183-226c-4320-ad46-ac0a1b03a5cf/' + s + '.png'

output_file = '/app/rendering/ffd06183-226c-4320-ad46-ac0a1b03a5cf/output_av.mp4'
output = av.open(output_file, 'w')

images = [cv2.imread( get_filename(i) ) for i in range(1,35)]


stream = output.add_stream(codec, fps)
stream.bit_rate = bitrate
stream.pix_fmt = fmt

for i, img in enumerate(images):
	# print( img )

	if not i:
		stream.height = img.shape[0]
		stream.width = img.shape[1]

	frame = av.VideoFrame.from_ndarray(img, format='bgr24')
	packet = stream.encode(frame)
	output.mux(packet)

output.close()

print('done \n')

The file is generated ok. When I check file properties, I get:

mediainfo --fullscan output_av.mp4
General
Count                                    : 330
Count of stream of this kind             : 1
Kind of stream                           : General
Kind of stream                           : General
Stream identifier                        : 0
Count of video streams                   : 1
Video_Format_List                        : MPEG-4 Visual
Video_Format_WithHint_List               : MPEG-4 Visual
Codecs Video                             : MPEG-4 Visual
Complete name                            : output_av.mp4
File name                                : output_av.mp4
File name                                : output_av
File extension                           : mp4
Format                                   : MPEG-4
Format                                   : MPEG-4
Format/Extensions usually used           : mov mp4 m4v m4a m4b m4p 3ga 3gpa 3gpp 3gp 3gpp2 3g2 k3g jpm jpx mqv ismv isma ismt f4a f4b f4v
Commercial name                          : MPEG-4
Format profile                           : Base Media
Internet media type                      : video/mp4
Codec ID                                 : isom
Codec ID                                 : isom (isom/iso2/mp41)
Codec ID/Url                             : http://www.apple.com/quicktime/download/standalone.html
CodecID_Compatible                       : isom/iso2/mp41
Codec                                    : MPEG-4
Codec                                    : MPEG-4
Codec/Extensions usually used            : mov mp4 m4v m4a m4b m4p 3ga 3gpa 3gpp 3gp 3gpp2 3g2 k3g jpm jpx mqv ismv isma ismt f4a f4b f4v
File size                                : 300278
File size                                : 293 KiB
File size                                : 293 KiB
File size                                : 293 KiB
File size                                : 293 KiB
File size                                : 293.2 KiB
Duration                                 : 1419
Duration                                 : 1 s 419 ms
Duration                                 : 1 s 419 ms
Duration                                 : 1 s 419 ms
Duration                                 : 00:00:01.419
Duration                                 : 00:00:01;10
Duration                                 : 00:00:01.419 (00:00:01;10)
Overall bit rate mode                    : VBR
Overall bit rate mode                    : Variable
Overall bit rate                         : 1692899
Overall bit rate                         : 1 693 kb/s
Frame rate                               : 23.976
Frame rate                               : 23.976 FPS
Frame count                              : 34
Stream size                              : 1005
Stream size                              : 1 005 Bytes (0%)
Stream size                              : 1 005 Bytes
Stream size                              : 1 005 Bytes
Stream size                              : 1 005 Bytes
Stream size                              : 1 005.0 Bytes
Stream size                              : 1 005 Bytes (0%)
Proportion of this stream                : 0.00335
HeaderSize                               : 36
DataSize                                 : 299281
FooterSize                               : 961
IsStreamable                             : No
File last modification date              : UTC 2018-11-28 14:22:57
File last modification date (local)      : 2018-11-28 17:22:57
Writing application                      : Lavf58.12.100
Writing application                      : Lavf58.12.100

Video
Count                                    : 344
Count of stream of this kind             : 1
Kind of stream                           : Video
Kind of stream                           : Video
Stream identifier                        : 0
StreamOrder                              : 0
ID                                       : 1
ID                                       : 1
Format                                   : MPEG-4 Visual
Commercial name                          : MPEG-4 Visual
Format profile                           : Simple@L1
Format settings, BVOP                    : No
Format settings, BVOP                    : No
Format settings, QPel                    : No
Format settings, QPel                    : No
Format settings, GMC                     : 0
Format settings, GMC                     : No warppoints
Format settings, Matrix                  : Default (H.263)
Format settings, Matrix                  : Default (H.263)
Internet media type                      : video/MP4V-ES
Codec ID                                 : mp4v-20
Codec                                    : MPEG-4V
Codec                                    : MPEG-4 Visual
Codec/Family                             : MPEG-4V
Codec/CC                                 : 20
Codec profile                            : Simple@L1
Codec settings, Packet bitstream         : No
Codec settings, BVOP                     : No
Codec settings, QPel                     : No
Codec settings, GMC                      : 0
Codec settings, GMC                      : No warppoints
Codec settings, Matrix                   : Default (H.263)
Duration                                 : 1419
Duration                                 : 1 s 419 ms
Duration                                 : 1 s 419 ms
Duration                                 : 1 s 419 ms
Duration                                 : 00:00:01.419
Duration                                 : 00:00:01;10
Duration                                 : 00:00:01.419 (00:00:01;10)
Bit rate mode                            : VBR
Bit rate mode                            : Variable
Bit rate                                 : 1688322
Bit rate                                 : 1 688 kb/s
Maximum bit rate                         : 8000000
Maximum bit rate                         : 8 000 kb/s
Width                                    : 640
Width                                    : 640 pixels
Height                                   : 360
Height                                   : 360 pixels
Sampled_Width                            : 640
Sampled_Height                           : 360
Pixel aspect ratio                       : 1.000
Display aspect ratio                     : 1.778
Display aspect ratio                     : 16:9
Rotation                                 : 0.000
Frame rate mode                          : CFR
Frame rate mode                          : Constant
Frame rate                               : 23.976
Frame rate                               : 23.976 (23976/1000) FPS
FrameRate_Num                            : 23976
FrameRate_Den                            : 1000
Frame count                              : 34
Resolution                               : 8
Resolution                               : 8 bits
Colorimetry                              : 4:2:0
Color space                              : YUV
Chroma subsampling                       : 4:2:0
Chroma subsampling                       : 4:2:0
Bit depth                                : 8
Bit depth                                : 8 bits
Scan type                                : Progressive
Scan type                                : Progressive
Interlacement                            : PPF
Interlacement                            : Progressive
Compression mode                         : Lossy
Compression mode                         : Lossy
Bits/(Pixel*Frame)                       : 0.306
Stream size                              : 299273
Stream size                              : 292 KiB (100%)
Stream size                              : 292 KiB
Stream size                              : 292 KiB
Stream size                              : 292 KiB
Stream size                              : 292.3 KiB
Stream size                              : 292 KiB (100%)
Proportion of this stream                : 0.99665
Writing library                          : Lavc58.18.100
Writing library                          : Lavc58.18.100

I expect this to be a h264, but this is not.
After checking out other examples, I assumed I can use h264 for my video.
So, is this possible to make and h264 file?

[jlaine]

Your example works fine for me, use ffprobe and it will tell you the output is H.264.

One thing your example is lacking is a "flush" on the output. Also you can just use python's standard formatting mechanisms instead of padding the numbers yourself.

import os
import cv2
import av

images = [cv2.imread('/some/path/%.4d.png' % i) for i in range(1, 35)]

output = av.open('output_av.mp4', 'w')
stream = output.add_stream('h264', '23.976')
stream.bit_rate = 8000000

for i, img in enumerate(images):
    frame = av.VideoFrame.from_ndarray(img, format='bgr24')
    packet = stream.encode(frame)
    output.mux(packet)

# flush
packet = stream.encode(None)
output.mux(packet)

output.close()