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Valkaama DVD Label
4 octobre 2011, par
Mis à jour : Février 2013
Langue : English
Type : Image
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Podcasting Legal guide
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Mis à jour : Mai 2011
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Autres articles (58)
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Les autorisations surchargées par les plugins
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Sur d’autres sites (11773)
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ffmpeg : stream copy from .mxf into NLE-compatible format
9 juin 2013, par DavidBecause my NLE software does not support the .mxf-files from Canon XF100 I need to convert them into a supported format.
As far as I know, mxf-files are just another container format for mpeg2 streams, so it would be really nice to extract the streams and place them into another container (without reencoding).
I think ffmpeg can do this – correct me if I'm wrong – by running the following command :
ffmpeg -i in.mxf -vcodec copy out.m2ts (or .ts, .mts, ...)
ffmpeg finishes without errors after about 2 seconds (in.mxf is abut 170mb) :
c:\video>c:\ffmpeg\bin\ffmpeg -i in.MXF -vcodec copy out.m2ts
ffmpeg version N-53680-g0ab9362 Copyright (c) 2000-2013 the FFmpeg developers
built on May 30 2013 12:14:03 with gcc 4.7.3 (GCC)
configuration: --enable-gpl --enable-version3 --disable-w32threads --enable-av
isynth --enable-bzlib --enable-fontconfig --enable-frei0r --enable-gnutls --enab
le-iconv --enable-libass --enable-libbluray --enable-libcaca --enable-libfreetyp
e --enable-libgsm --enable-libilbc --enable-libmodplug --enable-libmp3lame --ena
ble-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg --enable-l
ibopus --enable-librtmp --enable-libschroedinger --enable-libsoxr --enable-libsp
eex --enable-libtheora --enable-libtwolame --enable-libvo-aacenc --enable-libvo-
amrwbenc --enable-libvorbis --enable-libvpx --enable-libx264 --enable-libxavs --
enable-libxvid --enable-zlib
libavutil 52. 34.100 / 52. 34.100
libavcodec 55. 12.102 / 55. 12.102
libavformat 55. 8.100 / 55. 8.100
libavdevice 55. 2.100 / 55. 2.100
libavfilter 3. 73.100 / 3. 73.100
libswscale 2. 3.100 / 2. 3.100
libswresample 0. 17.102 / 0. 17.102
libpostproc 52. 3.100 / 52. 3.100
Guessed Channel Layout for Input Stream #0.1 : mono
Guessed Channel Layout for Input Stream #0.2 : mono
Input #0, mxf, from 'in.MXF':
Metadata:
uid : 1bb23c97-6205-4800-80a2-e00002244ba7
generation_uid : 1bb23c97-6205-4800-8122-e00002244ba7
company_name : CANON
product_name : XF100
product_version : 1.00
product_uid : 060e2b34-0401-010d-0e15-005658460100
modification_date: 2013-01-06 11:05:02
timecode : 01:42:14:22
Duration: 00:00:28.32, start: 0.000000, bitrate: 51811 kb/s
Stream #0:0: Video: mpeg2video (4:2:2), yuv422p, 1920x1080 [SAR 1:1 DAR 16:9
], 25 fps, 25 tbr, 25 tbn, 50 tbc
Stream #0:1: Audio: pcm_s16le, 48000 Hz, mono, s16, 768 kb/s
Stream #0:2: Audio: pcm_s16le, 48000 Hz, mono, s16, 768 kb/s
Output #0, mpegts, to 'out.m2ts':
Metadata:
uid : 1bb23c97-6205-4800-80a2-e00002244ba7
generation_uid : 1bb23c97-6205-4800-8122-e00002244ba7
company_name : CANON
product_name : XF100
product_version : 1.00
product_uid : 060e2b34-0401-010d-0e15-005658460100
modification_date: 2013-01-06 11:05:02
timecode : 01:42:14:22
encoder : Lavf55.8.100
Stream #0:0: Video: mpeg2video, yuv422p, 1920x1080 [SAR 1:1 DAR 16:9], q=2-3
1, 25 fps, 90k tbn, 25 tbc
Stream #0:1: Audio: mp2, 48000 Hz, mono, s16, 128 kb/s
Stream mapping:
Stream #0:0 -> #0:0 (copy)
Stream #0:1 -> #0:1 (pcm_s16le -> mp2)
Press [q] to stop, [?] for help
frame= 532 fps=0.0 q=-1.0 size= 143511kB time=00:00:21.25 bitrate=55314.1kbits
frame= 561 fps=435 q=-1.0 size= 151254kB time=00:00:22.42 bitrate=55242.0kbits
frame= 586 fps=314 q=-1.0 size= 158021kB time=00:00:23.41 bitrate=55288.0kbits
frame= 609 fps=255 q=-1.0 size= 164182kB time=00:00:24.34 bitrate=55235.4kbits
frame= 636 fps=217 q=-1.0 size= 171463kB time=00:00:25.42 bitrate=55235.1kbits
frame= 669 fps=194 q=-1.0 size= 180133kB time=00:00:26.72 bitrate=55226.3kbits
frame= 699 fps=173 q=-1.0 size= 188326kB time=00:00:27.92 bitrate=55256.6kbits
frame= 708 fps=169 q=-1.0 Lsize= 190877kB time=00:00:28.30 bitrate=55233.6kbit
s/s
video:172852kB audio:442kB subtitle:0 global headers:0kB muxing overhead 10.1461
18%Unfortunately the output file turns out to be displayed correctly only by vlc player.
My NLE-software (Cyberlink Power Director) is able to open the file but most of the picture is green. Only a few pixels on the left edge show the original video :Any ideas how to solve that problem ? Is there a better way to use .mxf-files in NLE-software without native support ?
thanks in advance
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Turn off sw_scale conversion to planar YUV 32 byte alignment requirements
8 novembre 2022, par flanselI am experiencing artifacts on the right edge of scaled and converted images when converting into planar YUV pixel formats with sw_scale. I am reasonably sure (although I can not find it anywhere in the documentation) that this is because sw_scale is using an optimization for 32 byte aligned lines, in the destination. However I would like to turn this off because I am using sw_scale for image composition, so even though the destination lines may be 32 byte aligned, the output image may not be.


Example.


Full output frame is 1280x720 yuv422p10le. (this is 32 byte aligned)
However into the top left corner I am scaling an image with an outwidth of 1280 / 3 = 426.
426 in this format is not 32 byte aligned, but I believe sw_scale sees that the output linesize is 32 byte aligned and overwrites the width of 426 putting garbage in the next 22 bytes of data thinking this is simply padding when in my case this is displayable area.


This is why I need to actually disable this optimization or somehow trick sw_scale into believing it does not apply while keeping intact the way the program works, which is otherwise fine.


I have tried adding extra padding to the destination lines so they are no longer 32 byte aligned,
this did not help as far as I can tell.


Edit with code Example. Rendering omitted for ease of use.
Also here is a similar issue, unfortunately as I stated there fix will not work for my use case. https://github.com/obsproject/obs-studio/pull/2836


Use the commented line of code to swap between a output width which is and isnt 32 byte aligned.


#include "libswscale/swscale.h"
#include "libavutil/imgutils.h"
#include "libavutil/pixelutils.h"
#include "libavutil/pixfmt.h"
#include "libavutil/pixdesc.h"
#include 
#include 
#include 

int main(int argc, char **argv) {

/// Set up a 1280x720 window, and an item with 1/3 width and height of the window.
int window_width, window_height, item_width, item_height;
window_width = 1280;
window_height = 720;
item_width = (window_width / 3);
item_height = (window_height / 3);

int item_out_width = item_width;
/// This line sets the item width to be 32 byte aligned uncomment to see uncorrupted results
/// Note %16 because outformat is 2 bytes per component
//item_out_width -= (item_width % 16);

enum AVPixelFormat outformat = AV_PIX_FMT_YUV422P10LE;
enum AVPixelFormat informat = AV_PIX_FMT_UYVY422;
int window_lines[4] = {0};
av_image_fill_linesizes(window_lines, outformat, window_width);

uint8_t *window_planes[4] = {0};
window_planes[0] = calloc(1, window_lines[0] * window_height);
window_planes[1] = calloc(1, window_lines[1] * window_height);
window_planes[2] = calloc(1, window_lines[2] * window_height); /// Fill the window with all 0s, this is green in yuv.


int item_lines[4] = {0};
av_image_fill_linesizes(item_lines, informat, item_width);

uint8_t *item_planes[4] = {0};
item_planes[0] = malloc(item_lines[0] * item_height);
memset(item_planes[0], 100, item_lines[0] * item_height);

struct SwsContext *ctx;
ctx = sws_getContext(item_width, item_height, informat,
 item_out_width, item_height, outformat, SWS_FAST_BILINEAR, NULL, NULL, NULL);

/// Check a block in the normal region
printf("Pre scale normal region %d %d %d\n", (int)((uint16_t*)window_planes[0])[0], (int)((uint16_t*)window_planes[1])[0],
 (int)((uint16_t*)window_planes[2])[0]);

/// Check a block in the corrupted region (should be all zeros) These values should be out of the converted region
int corrupt_offset_y = (item_out_width + 3) * 2; ///(item_width + 3) * 2 bytes per component Y PLANE
int corrupt_offset_uv = (item_out_width + 3); ///(item_width + 3) * (2 bytes per component rshift 1 for horiz scaling) U and V PLANES

printf("Pre scale corrupted region %d %d %d\n", (int)(*((uint16_t*)(window_planes[0] + corrupt_offset_y))),
 (int)(*((uint16_t*)(window_planes[1] + corrupt_offset_uv))), (int)(*((uint16_t*)(window_planes[2] + corrupt_offset_uv))));
sws_scale(ctx, (const uint8_t**)item_planes, item_lines, 0, item_height,window_planes, window_lines);

/// Preform same tests after scaling
printf("Post scale normal region %d %d %d\n", (int)((uint16_t*)window_planes[0])[0], (int)((uint16_t*)window_planes[1])[0],
 (int)((uint16_t*)window_planes[2])[0]);
printf("Post scale corrupted region %d %d %d\n", (int)(*((uint16_t*)(window_planes[0] + corrupt_offset_y))),
 (int)(*((uint16_t*)(window_planes[1] + corrupt_offset_uv))), (int)(*((uint16_t*)(window_planes[2] + corrupt_offset_uv))));

return 0;



}


Example Output:

//No alignment
Pre scale normal region 0 0 0
Pre scale corrupted region 0 0 0
Post scale normal region 400 400 400
Post scale corrupted region 512 36865 36865

//With alignment
Pre scale normal region 0 0 0
Pre scale corrupted region 0 0 0
Post scale normal region 400 400 400
Post scale corrupted region 0 0 0



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hls fails to play m3u8 playlist with videojs
9 novembre 2020, par charlieI created an hls stream from yuv frames with ffmpeg which appears to work just fine. It creates a playlist and updates that, and all .ts files as expected. However even videojs refuses to play it, and I really run out of ideas, probably missing the obvious ?


First, the m3u8 list which is continuously updated :


#EXTM3U
#EXT-X-VERSION:3
#EXT-X-TARGETDURATION:2
#EXT-X-MEDIA-SEQUENCE:190
#EXTINF:2.000000,
test190.ts
#EXTINF:2.000000,
test191.ts
#EXTINF:2.000000,
test192.ts
#EXTINF:2.000000,
test193.ts
#EXTINF:2.000000,
test194.ts



Those .ts files exist and have sizes of approx 250 kBytes.
Then, I open this standard videojs html file (residing in the same directory) :








 


 <h1>VSTream</h1>

 
 <source src="test.m3u8" type="application/x-mpegURL">
 
 
 <code class="echappe-js"><script src='http://stackoverflow.com/feeds/tag/video.min.js'></script>

<script src='http://stackoverflow.com/feeds/tag/videojs-http-streaming.min.js'></script>

 
<script>&#xA; var player = videojs(&#x27;my_video_1&#x27;);&#xA; </script>

 




I open this in Firefox (or Chrome, or Edge, none works) and use its debugger which in the console shows :




VIDEOJS : WARN : A plugin named "reloadSourceOnError" already exists.
You may want to avoid re-registering plugins ! video.min.js:12:977
Specified “type” attribute of “application/x-mpegURL” is not
supported. Load of media resource test.m3u8 failed. vstream.html All
candidate resources failed to load. Media load paused. vstream.html
XML Parsing Error : syntax error Location : file :///C :/test/test.m3u8
Line Number 1, Column 1 : 2 test.m3u8:1:1 MouseEvent.mozPressure is
deprecated. Use PointerEvent.pressure instead. video.min.js:12:9031
VIDEOJS : ERROR : (CODE:3 MEDIA_ERR_DECODE) Playback cannot continue. No
available working or supported playlists. Object code : 3, message :
"Playback cannot continue. No available working or supported
playlists." video.min.js:12:977




This doesn't make much sense to me. Why would it throw an XML parsing error for an m3u8 file ? Of course, the MEDIA_ERR_DECODE points in some direction, but the same problem persists with fMP4 files.


The relevant ffmpeg c++ code (format is "hls" and formatContext works well in other scenarios, gop is 2) :


AVDictionary* options = 0;
 if (fragmented)
 {
 // type
 if (codecID == AV_CODEC_ID_H264)
 av_dict_set (&options, "hls_segment_type", "fmp4", 0);
 else
 av_dict_set (&options, "hls_segment_type", "mpegts", 0);

 av_dict_set (&options, "hls_time", "2.0", 0);
 av_dict_set_int (&options, "hls_list_size", 5, 0);
 av_dict_set (&options, "hls_flags", "delete_segments", 0);
 }

 int ret = avformat_write_header (formatContext, &options);



...which returns success. Then writing frames


int ret = avcodec_send_frame (videoStream->codecContext, frame);
 av_init_packet (avPacket);
 AVRational timeBase = videoStream->getTimeBase ();
 avPacket->stream_index = streams.indexOf (videoStream);
 ret = avcodec_receive_packet (videoStream->codecContext, avPacket);
 avPacket->duration = av_rescale_q (1, videoStream->codecContext->time_base, videoStream->getTimeBase ());
 pts += avPacket->duration;
 avPacket->pts = pts;
 avPacket->dts = pts; // AV_NOPTS_VALUE;
 ret = av_interleaved_write_frame (formatContext, avPacket);



(videoStream here is an internal object representing the avstream).
I've omitted error checks for clarity. All return values show success.
Thanks for any help on this !