Hi, The 20 bits are located in the low 20-bits of the 32-bit word (like SNDRV_PCM_FORMAT_x24_xE where the 24-bit sample is located in the low 24-bits in 32-bit word. Thanks. -----Original Message----- From: Jaroslav Kysela [mailto:perex@xxxxxxx] Sent: Monday, October 23, 2006 8:43 AM To: Assaf Hoffman Cc: alsa-devel@xxxxxxxxxxxxxxxxxxxxx Subject: Re: PCM format 20 bit On Mon, 23 Oct 2006, Assaf Hoffman wrote: > Thank you, for your answer. > I do not understand how does it work? Obviously, the ALSA stack does not > have such format, and by trying to extract the buffer (capture example) > the stack will assume 32-bit sample width, getting trash on the lower 12 > bits. Could you describe exactly the location for 20-bit samples (use a byte table) in the DMA buffer, as your hw expects it? It's not obvious from your question. Jaroslav > -----Original Message----- > From: Giuliano Pochini [mailto:pochini@xxxxxxxx] > Sent: Sunday, October 22, 2006 8:56 PM > To: Assaf Hoffman > Cc: alsa-devel@xxxxxxxxxxxxxxxxxxxxx; Rita Shtern > Subject: Re: PCM format 20 bit > Importance: Low > > On Sun, 22 Oct 2006 18:11:55 +0200 > "Assaf Hoffman" <hoffman@xxxxxxxxxxx> wrote: > > > My HW supports 20-bit sample using 32-bit phy frame. As I understand, > > the only way the ALSA supports the 20-bit sample is 24-bit frame > > (SNDRV_PCM_FORMAT_x20_3xE). > > > > Please advice. > > If it's 20 bits left-aligned in 32 bits, you can use S32_LE or similar > formats. For example the old echoaudio cards based on the DSP 56301 use > S32_LE but only the upper 20 bits contain data. > > > -- > Giuliano. > > ------------------------------------------------------------------------ - > Using Tomcat but need to do more? Need to support web services, security? > Get stuff done quickly with pre-integrated technology to make your job easier > Download IBM WebSphere Application Server v.1.0.1 based on Apache Geronimo > http://sel.as-us.falkag.net/sel?cmd=lnk&kid=120709&bid=263057&dat=121642 > _______________________________________________ > Alsa-devel mailing list > Alsa-devel@xxxxxxxxxxxxxxxxxxxxx > https://lists.sourceforge.net/lists/listinfo/alsa-devel > Jaroslav ----- Jaroslav Kysela <perex@xxxxxxx> Linux Kernel Sound Maintainer ALSA Project, SUSE Labs ------------------------------------------------------------------------- Using Tomcat but need to do more? Need to support web services, security? Get stuff done quickly with pre-integrated technology to make your job easier Download IBM WebSphere Application Server v.1.0.1 based on Apache Geronimo http://sel.as-us.falkag.net/sel?cmd=lnk&kid=120709&bid=263057&dat=121642 _______________________________________________ Alsa-devel mailing list Alsa-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.sourceforge.net/lists/listinfo/alsa-devel
