MPEG stills for VCD and SVCD - Info and a preliminary automa

[tb]

Here is some info I collected about converting bitmaps into MPEG stills plus a script for an automated conversion using TMPEGEnc. Some details on the properties of MPEG stills have been posted here already. Additionally, I used bbinfo, BitRate Viewer, and a program called MPEGID from Manzanita Systems to compare the working MPEG stills from hvr's site and some produced by NERO with the TMPEGEnc results until they matched as closely as possible.

The input bitmaps (704x576 pixels for PAL, 704x480 pixels for NTSC) were created with PaintShop Pro. For SVCD I finally used the following main settings:

Size: 704x576 (PAL) resp. 704x480 (NTSC)
Aspect ratio: 4:3
Frame rate: 25 fps (PAL) resp. 29,97 fps (NTSC)
Rate control mode: MVBR, 9800 bps (= max DVD rate)
VBV buffer size: 112
GOP structure: I pictures only
Stream type: MPEG-2 System (Video only), MPEG-2 Super VideoCD (VBR)

The resulting MPEG-2 program stream has one video elementary stream. The stream ID is 0xE0 and has to be patched to 0xE1.

For VCD it's a bit more complicate as the MPEG-1 program stream contains two video elementary streams. So at first two separate video elementary streams have to be produced with the following TMPEGEnc settings:
Size: 352x288 (stream #1, PAL), 704x576 (stream #2, PAL) resp. 352x240 (stream #1, NTSC), 704x480 (stream #2, NTSC)
Aspect ratio: 4:3
Frame rate: 25 fps (PAL), 29,97 fps (NTSC)
Rate control mode: CBR, 8000 bps
VBV buffer size: 0 (automatic)
GOP structure: I pictures only
Stream type: Video only

The two resulting MPEG-1 video elementary streams have to be multiplexed into a program stream by using the TMPEGEnc Tools with these settings: Third tab (Multiplex), Type: MPEG-1 Video-CD. The stream IDs have to be patched from 0xE1 to 0xE2 and from 0xE0 to 0xE1.

As all this is a quite tedious procedure, I wrote a simple script (actually four) using Phantom for Windows to have a convenient temporary solution (temporary because the programs used are only 30 days trials, I don't know if the stills are really compliant, and a final solution should be made using a real programming language). The script launches TMPEGEnc to produce both VCD and SVCD mpeg stills for PAL resp. NTSC and also patches the stream IDs.

These stills work perfectly using VCDImager for authoring and CDRWIN for burning on my Afreey LD2060 (FW 3.4). They also work with WinDVD, which actually doesn't care about the correct stream IDs. If some of you would like to test if they also work with other stand alone players, you can download some sample MPEG stills. The Phantom scripts are also included, so you may also try the automated conversion of your own bitmaps.

The Phantom scripts are kept as simple as possible (i.e. no error checks, no GUI) as I think this is a temporary solution only. Therefore, the following folder structure is essential:

Download the zip file BMP2MPG.ZIP and unzip to c:\ . Be sure the 'Use folder names' checkbox is checked. You should then have a folder BMP2MPG in c:\ with four sub folders BMP, MPG, MPG_STILLS and TMPEGEnc. The latter only contains six templates and two batch files, so you have to add a copy of a TMPEGEnc.exe file to this folder (version 12i, the unlimited MPEG-2 version 12a doesn't support batch handling per command line). Note: Run the new copy of TMPEGEnc.exe from this folder once, start any MPEG-2 encoding and click away the two warning messages, otherwise the scripts will hang at this point. I was too lazy to add a handler for this to the scripts. The BMP, MPG, and MPG_STILLS folders contain sample files. The BMP2MPG folder contains four Phantom scripts, namely BMP2MPG_PAL_GE.TXT, BMP2MPG_PAL_US.TXT, BMP2MPG_NTSC_GE.TXT and BMP2MPG_NTSC_US.TXT. Note: There is a Phantom problem related to the keyboard layout (colon and backslash assignment). That's why there are two different scripts for either keyboard layout (GE for German standard layout and US for US 101 layout) for both PAL and NTSC. The US version should work, although I only tested this with my German keyboard with a US layout activated in the Windows system control. Many other language layouts should also work with one of the two scripts.

You have to install Phantom for Windows to run the script. Then just open the appropriate BMP2MPG_xx.TXT script and click on the play button. You will see some TMPEGEnc windows opening and closing and after a few seconds the respective files in the MPG and MPG_STILLS sub folder have been updated. The MENU_VCD_PAL.MPG and MENU_SVCD_PAL.MPG (resp. xx_NTSC.MPG) files are the ready-to-use stills. The other files in the MPG sub folder are just the above described files produced by TMPEGEnc and left here for testing.

If you want to produce your own stills, create a 704x576 resp. 704x480 sized bitmap, name the file Menu_704x576.bmp resp. Menu_704x480.bmp, place it in the BMP sub folder and run the script. The existing MPEG stills will be overwritten each time, so copy them to another folder if you want to keep them. BTW, you can make exe files from the scripts. For me this only worked with the latest Phantom beta version 12m. Executables made with previous versions did not work correctly and sometimes even locked up Windows.

The specialists amongst you should be able to write a real program to do the conversion. I don't know if one can directly access the TMPEGEnc encoding/multiplexing subroutines or if any other encoders/muxers could be used for this. If so, how about integrating all this into VCDImager or into one of the new GUIs?

hvr, do you have a reliable method to check if the stills are compliant? There are some differences left between my ones and the ones from your site resp. the ones ripped from VCDs authored with NERO. Does this program which can't produce compliant VCDs at least produce compliant MPEG stills?

For example, bbinfo shows an additional pack start directly followed by a padding stream packet at the end of your SVCD MPEG still (hvrlab_pal_mpeg2.mpg). Also, timing and muxrates are different. The two streams of my VCD MPEG still are muxed alternately rather than first all 0xE1 followed by all 0xE2 packets as seen in a NERO VCD MPEG still. I limited the bitrate of the VCD video streams to 8000 bps since 9800 bps caused a buffer underflow warning in the TMPEGEnc multiplexer. Anyway, I found some 8000 bps stills on your demo VCD, others have 9800 bps; this appears not to be critical as long as the bitrate is high enough to avoid artifacts. After all, I haven't found any detailed information on what makes an MPEG still compliant for (S)VCDs. Anything available?


Download links:

MPEGID from Manzanita Systems
http://www.lilapple.com/
30 days trial version 1.0.2
Note: There is also a command line muxer which allows to preset the stream IDs.

Phantom for Windows
http://www.p1.com/index.html
30 days trial version 1.5m

BMP2MPG Phantom scripts, sample BMPs, and sample MPEG stills
http://www.tb-electronic.de/video/video.html
Download the BMP2MPG.ZIP file

[Betamax]

Thanks !
I used your procedure, studied the scripts and so.
But because the tools you use to create a still aren't free software, I created a procedure my own.
Use VCDwizard to create the still (in conjunction with your favorite graphical editor, like PaintShop Pro is my favorite - and in conjunction with TMPGenc).
VCDwizard is free software. The patching of the final mpeg to a compliant still can be done insight VCDwizard (which I added as "internal" tool).
The whole procedure, how to create a still is explained in the HELP of VCDwizard (see "contents" | "Tools - Tips - Tricks").

The first ALPHA version, include advanched HELP, will be available shortly.

Regards,