Re: libjpeg8c vs libjpeg-turbo with libjpeg8 compat on
On Fri, Oct 28, 2011 at 12:05:38PM +0300, Riku Voipio wrote: > On 27 October 2011 12:38, Matthias Klose wrote: > > - A test rebuild for packages build-depending on libjpeg*-dev. > > Not sure if this will catch all issues, but it's a start. > > That should give an estimate for sourceful and sourceless > > changes needed, and for which packages you'll have to > > maintain a delta compared to Debian. > > Since libjpeg-turbo is API/ABI compatible, it would not even require a > rebuild. Only if it's packaged such that the libjpeg-turbo source package builds a libjpeg8 binary package. -- Colin Watson [cjwat...@ubuntu.com] -- ubuntu-devel mailing list ubuntu-devel@lists.ubuntu.com Modify settings or unsubscribe at: https://lists.ubuntu.com/mailman/listinfo/ubuntu-devel
Re: libjpeg8c vs libjpeg-turbo with libjpeg8 compat on
On 27 October 2011 12:38, Matthias Klose wrote: > I doubt that Ubuntu will reconsider this for Precise, but I see that you did > schedule a session for UDS/Connect [1]. It would be good, if you could provide > relevant information for the session: > > - performance data from your wiki in a precise/12.04 environment, > not just for arm, but for all supported Ubuntu architectures. > Performance data from a natty environment doesn't really help. > > How does this compare to a libjpeg8 targeted to newer CPUs? > Such a library could be used via hwcap. Fedora switched to libjpeg-turbo and reports in their release notes: "The libjpeg library has been replaced by libjpeg-turbo library which has same API/ABI but is at least twice faster on all primary architectures and about 25% faster on secondary architectures." > - A test rebuild for packages build-depending on libjpeg*-dev. > Not sure if this will catch all issues, but it's a start. > That should give an estimate for sourceful and sourceless > changes needed, and for which packages you'll have to > maintain a delta compared to Debian. Since libjpeg-turbo is API/ABI compatible, it would not even require a rebuild. This makes the transition actually smoother than the transition to libjpeg8 fork of the original libjpeg. Riku -- ubuntu-devel mailing list ubuntu-devel@lists.ubuntu.com Modify settings or unsubscribe at: https://lists.ubuntu.com/mailman/listinfo/ubuntu-devel
Re: libjpeg8c vs libjpeg-turbo with libjpeg8 compat on
On 10/26/2011 10:54 PM, Tom Gall wrote: > In prep for Linaro Connect & the Ubuntu Developers Summit next week > I've put together some performance measurements comparing libjpeg8c > and libjpeg-turbo compiled with it's libjpeg8 compatibility setting. > Quality settings of 95 and 75 are used. Image sizes used are 640x480 > and 3136x2352. > > Hardware used includes the imx53 QuickStart board by freescale and an > intel core 2 duo in my Lenovo T400. > > The results can be found here including both the raw numbers and pretty > graphs. > > https://wiki.linaro.org/TomGall/LibJpeg8 > > It is my hope that at LC/UDS we will be able to use these numbers to > convince ubuntu to reconsider it's switch to libjpeg8 and instead move > to libjpeg-turbo. The 2x-4x across the board performance improvement > story is compelling not to mention the technical side of it as well. I doubt that Ubuntu will reconsider this for Precise, but I see that you did schedule a session for UDS/Connect [1]. It would be good, if you could provide relevant information for the session: - performance data from your wiki in a precise/12.04 environment, not just for arm, but for all supported Ubuntu architectures. Performance data from a natty environment doesn't really help. How does this compare to a libjpeg8 targeted to newer CPUs? Such a library could be used via hwcap. - A test rebuild for packages build-depending on libjpeg*-dev. Not sure if this will catch all issues, but it's a start. That should give an estimate for sourceful and sourceless changes needed, and for which packages you'll have to maintain a delta compared to Debian. Thanks, Matthias [1] https://blueprints.launchpad.net/libjpeg-turbo/+spec/linaro-gfxmm-libjpeg-turbo -- ubuntu-devel mailing list ubuntu-devel@lists.ubuntu.com Modify settings or unsubscribe at: https://lists.ubuntu.com/mailman/listinfo/ubuntu-devel
