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Hi All, I have been trying to display decoded video using the DDK libraries on DM642. The output of the decoder is YUV 4:2:0 format. However for displaying it correctly on the VGA Monitor, I need to convert it to RGB for proper color. The documentation seems to suggest that feeding the YUV directly should also work but the color is not correct when I directly feed yuv data. Even the example program which uses YUV for XGA displays incorrect colors. My guess is that the yuv works only for SDTV and for monitors Color space conversion in software is required. Any experiences/hints would be very valueble. Regards Piyush ===== ************************************** And---"A blind Understanding!" Heav'n replied. Piyush Kaul http://www.geocities.com/piyushkaul __________________________________ |
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YUV format for Video Driver in DM642
Started by ●May 21, 2004
Reply by ●May 22, 20042004-05-22
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Yes VGA will only take RGB (565) with R being 5 bits, G being 6 bits and B being 5 bits. Regds JS -----Original Message----- From: piyush kaul [mailto:] Sent: Friday, May 21, 2004 4:30 AM To: Subject: [c6x] YUV format for Video Driver in DM642 Hi All, I have been trying to display decoded video using the DDK libraries on DM642. The output of the decoder is YUV 4:2:0 format. However for displaying it correctly on the VGA Monitor, I need to convert it to RGB for proper color. The documentation seems to suggest that feeding the YUV directly should also work but the color is not correct when I directly feed yuv data. Even the example program which uses YUV for XGA displays incorrect colors. My guess is that the yuv works only for SDTV and for monitors Color space conversion in software is required. Any experiences/hints would be very valueble. Regards Piyush ===== ************************************** And---"A blind Understanding!" Heav'n replied. Piyush Kaul http://www.geocities.com/piyushkaul __________________________________ _____________________________________ Note: If you do a simple "reply" with your email client, only the author of this message will receive your answer. You need to do a "reply all" if you want your answer to be distributed to the entire group. _____________________________________ About this discussion group: To Join: Send an email to To Post: Send an email to To Leave: Send an email to Archives: http://www.yahoogroups.com/group/c6x Other Groups: http://www.dsprelated.com Yahoo! Groups Links |
Reply by ●May 23, 20042004-05-23
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Piyush- > I have been trying to display decoded video using the > DDK libraries on DM642. The output of the decoder is > YUV 4:2:0 format. However for displaying it correctly > on the VGA Monitor, I need to convert it to RGB for > proper color. The documentation seems to suggest that > feeding the YUV directly should also work but the > color is not correct when I directly feed yuv data. > > Even the example program which uses YUV for XGA > displays incorrect colors. > > My guess is that the yuv works only for SDTV and for > monitors Color space conversion in software is > required. > Any experiences/hints would be very valueble. Below is some example source code that uses DirectDSP software and reads MPEG4 algorithm output from the DSK C6711 + IDK board combination. The MPEG4 algorithm is from Mecoso; this example shows D1 resolution about 12 frame/sec on the DSK board (relatively slow at 150 MHz). The GetMem() calls are DirectDSP API calls (actually a C++ class on top of the standard DSGetMem API call). Note the memcpy()'s to grab separate Y, Cb, Cr format data from DSP mem. Then there is a bunch more code (SetFrame call) to convert YCbCr data to RGB format suitable for display in a Win bitmap -- but I did not post that code. I hope this is helpful. -Jeff while (!g_DSP.GetFrameReady()); //Capture data and set current frame data //All sizes divided by four because we're reading 4-byte chunks //NOTE: Max read is 32768 bytes //Read Y data for (i=0; i<FrameSize-32768; i+2768) { g_DSP.GetMem(DS_GM_LINEAR_DATA, 0x80500008 + i, DS_GM_SIZE32, Data, 8192); memcpy(m_YUVData.Y + i, Data, 32768); } //Not an even number of 32768 byte chunks... if (i - FrameSize != 0) { //i -= 32768; g_DSP.GetMem(DS_GM_LINEAR_DATA, 0x80500008 + i, DS_GM_SIZE32, Data, (FrameSize - i) / 4); memcpy(m_YUVData.Y + i, Data, (FrameSize - i)); } //Read Cb data for (i=0; i<=FrameSize / 4-32768; i+2768) { g_DSP.GetMem(DS_GM_LINEAR_DATA, 0x80500008 + FrameSize + i, DS_GM_SIZE32, Data, 8192); memcpy(m_YUVData.Cb + i, Data, 32768); } //Not an even number of 32768 byte chunks... if (i - FrameSize / 4 != 0) { //i -= 32768; g_DSP.GetMem(DS_GM_LINEAR_DATA, 0x80500008 + FrameSize + i, DS_GM_SIZE32, Data, (FrameSize / 4 - i) / 4); memcpy(m_YUVData.Cb + i, Data, (FrameSize / 4 - i)); } //Read Cr Data for (i=0; i<=FrameSize / 4-32768; i+2768) { g_DSP.GetMem(DS_GM_LINEAR_DATA, 0x80500008 + FrameSize * 5 / 4 + i, DS_GM_SIZE32, Data, 8192); memcpy(m_YUVData.Cr + i, Data, 32768); } //Not an even number of 32768 byte chunks... if (i - FrameSize / 4 != 0) { //i -= 32768; g_DSP.GetMem(DS_GM_LINEAR_DATA, 0x80500008 + FrameSize * 5 / 4 + i, DS_GM_SIZE32, Data, (FrameSize / 4 - i) / 4); memcpy(m_YUVData.Cr + i, Data, (FrameSize / 4 - i)); } //Save to file if we have a file pointer if (pFile) { fwrite(m_YUVData.Y, FrameSize, 1, pFile); fwrite(m_YUVData.Cb, FrameSize / 4, 1, pFile); fwrite(m_YUVData.Cr, FrameSize / 4, 1, pFile); } //Set current frame data m_YUV.SetFrame(m_YUVData); //Force view to refresh ((CFrameWnd *)::AfxGetM |
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Reply by ●May 24, 20042004-05-24
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Hi Jeff, Thanks for the help. However I intend to use the EVM as a standalone system(unconnected to PC) and hence using any software like DirectDSP is out of question. Also the objective is to display real-time video through the video port on a Television or VGA Monitor and not through PC. Hence the code might not be relevent to my need as of now. I already have a reasonable implementation of real-time video display for VGA. However, as I communicated, I am not able to do without color-space conversion (YUV to RGB). As you might know, color-space conversion is highly intensive especially for large resolutions, hence my question whether it could be avoided. Sankaran suggests that it can not be avoided for VGA, hence I need to go with it atleast for VGA. Now need to look for TV. Regards Piyush --- Jeff Brower <> wrote: > Piyush- > > > I have been trying to display decoded video using > the > > DDK libraries on DM642. The output of the decoder > is > > YUV 4:2:0 format. However for displaying it > correctly > > on the VGA Monitor, I need to convert it to RGB > for > > proper color. The documentation seems to suggest > that > > feeding the YUV directly should also work but the > > color is not correct when I directly feed yuv > data. > > > > Even the example program which uses YUV for XGA > > displays incorrect colors. > > > > My guess is that the yuv works only for SDTV and > for > > monitors Color space conversion in software is > > required. > > Any experiences/hints would be very valueble. > > Below is some example source code that uses > DirectDSP software and reads MPEG4 > algorithm output from the DSK C6711 + IDK board > combination. The MPEG4 algorithm is > from Mecoso; this example shows D1 resolution about > 12 frame/sec on the DSK board > (relatively slow at 150 MHz). > > The GetMem() calls are DirectDSP API calls (actually > a C++ class on top of the > standard DSGetMem API call). Note the memcpy()'s to > grab separate Y, Cb, Cr format > data from DSP mem. Then there is a bunch more code > (SetFrame call) to convert YCbCr > data to RGB format suitable for display in a Win > bitmap -- but I did not post that > code. > > I hope this is helpful. > > -Jeff > > while (!g_DSP.GetFrameReady()); > > //Capture data and set current frame data > > //All sizes divided by four because we're reading > 4-byte chunks > //NOTE: Max read is 32768 bytes > > //Read Y data > for (i=0; i<FrameSize-32768; i+2768) { > g_DSP.GetMem(DS_GM_LINEAR_DATA, 0x80500008 + > i, DS_GM_SIZE32, Data, 8192); > memcpy(m_YUVData.Y + i, Data, 32768); > } > //Not an even number of 32768 byte chunks... > if (i - FrameSize != 0) { > //i -= 32768; > g_DSP.GetMem(DS_GM_LINEAR_DATA, 0x80500008 + > i, DS_GM_SIZE32, Data, (FrameSize > - i) / 4); > memcpy(m_YUVData.Y + i, Data, (FrameSize - > i)); > } > > //Read Cb data > for (i=0; i<=FrameSize / 4-32768; i+2768) { > g_DSP.GetMem(DS_GM_LINEAR_DATA, 0x80500008 + > FrameSize + i, DS_GM_SIZE32, Data, > 8192); > memcpy(m_YUVData.Cb + i, Data, 32768); > } > //Not an even number of 32768 byte chunks... > if (i - FrameSize / 4 != 0) { > //i -= 32768; > g_DSP.GetMem(DS_GM_LINEAR_DATA, 0x80500008 + > FrameSize + i, DS_GM_SIZE32, Data, > (FrameSize / 4 - i) / 4); > memcpy(m_YUVData.Cb + i, Data, (FrameSize / 4 > - i)); > } > > //Read Cr Data > for (i=0; i<=FrameSize / 4-32768; i+2768) { > g_DSP.GetMem(DS_GM_LINEAR_DATA, 0x80500008 + > FrameSize * 5 / 4 + i, > DS_GM_SIZE32, Data, 8192); > memcpy(m_YUVData.Cr + i, Data, 32768); > } > //Not an even number of 32768 byte chunks... > if (i - FrameSize / 4 != 0) { > //i -= 32768; > g_DSP.GetMem(DS_GM_LINEAR_DATA, 0x80500008 + > FrameSize * 5 / 4 + i, > DS_GM_SIZE32, Data, (FrameSize / 4 - i) / 4); > memcpy(m_YUVData.Cr + i, Data, (FrameSize / 4 > - i)); > } > > //Save to file if we have a file pointer > if (pFile) > { > fwrite(m_YUVData.Y, FrameSize, 1, pFile); > fwrite(m_YUVData.Cb, FrameSize / 4, 1, pFile); > fwrite(m_YUVData.Cr, FrameSize / 4, 1, pFile); > } > > //Set current frame data > m_YUV.SetFrame(m_YUVData); > > //Force view to refresh > ((CFrameWnd *)::AfxGetM > _____________________________________ > Note: If you do a simple "reply" with your email > client, only the author of this message will receive > your answer. You need to do a "reply all" if you > want your answer to be distributed to the entire > group. > > _____________________________________ > About this discussion group: > > To Join: Send an email to > To Post: Send an email to > > To Leave: Send an email to > Archives: http://www.yahoogroups.com/group/c6x > > Other Groups: http://www.dsprelated.com > > Yahoo! Groups Links > ===== ************************************** And---"A blind Understanding!" Heav'n replied. Piyush Kaul http://www.geocities.com/piyushkaul __________________________________ |
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Reply by ●May 24, 20042004-05-24
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Piyush- > Thanks for the help. > However I intend to use the EVM as a standalone > system(unconnected to PC) and hence using any software > like DirectDSP is out of question. Also the objective > is to display real-time video through the video port > on a Television or VGA Monitor and not through PC. > Hence the code might not be relevent to my need as of > now. Ok, sorry -- somehow I did not realize you are staying self-contained on the board. Good luck... we are very lucky to have Sankaran's help, that's for sure. -Jeff > I already have a reasonable implementation of > real-time video display for VGA. However, as I > communicated, I am not able to do without color-space > conversion (YUV to RGB). As you might know, > color-space conversion is highly intensive > especially for large resolutions, hence my question > whether it could be avoided. > Sankaran suggests that it can not be avoided for VGA, > hence I need to go with it atleast for VGA. Now need > to look for TV. > > Regards > Piyush > --- Jeff Brower <> wrote: > > Piyush- > > > > > I have been trying to display decoded video using > > the > > > DDK libraries on DM642. The output of the decoder > > is > > > YUV 4:2:0 format. However for displaying it > > correctly > > > on the VGA Monitor, I need to convert it to RGB > > for > > > proper color. The documentation seems to suggest > > that > > > feeding the YUV directly should also work but the > > > color is not correct when I directly feed yuv > > data. > > > > > > Even the example program which uses YUV for XGA > > > displays incorrect colors. > > > > > > My guess is that the yuv works only for SDTV and > > for > > > monitors Color space conversion in software is > > > required. > > > Any experiences/hints would be very valueble. > > > > Below is some example source code that uses > > DirectDSP software and reads MPEG4 > > algorithm output from the DSK C6711 + IDK board > > combination. The MPEG4 algorithm is > > from Mecoso; this example shows D1 resolution about > > 12 frame/sec on the DSK board > > (relatively slow at 150 MHz). > > > > The GetMem() calls are DirectDSP API calls (actually > > a C++ class on top of the > > standard DSGetMem API call). Note the memcpy()'s to > > grab separate Y, Cb, Cr format > > data from DSP mem. Then there is a bunch more code > > (SetFrame call) to convert YCbCr > > data to RGB format suitable for display in a Win > > bitmap -- but I did not post that > > code. > > > > I hope this is helpful. > > > > -Jeff > > > > > > > > while (!g_DSP.GetFrameReady()); > > > > //Capture data and set current frame data > > > > //All sizes divided by four because we're reading > > 4-byte chunks > > //NOTE: Max read is 32768 bytes > > > > //Read Y data > > for (i=0; i<FrameSize-32768; i+2768) { > > g_DSP.GetMem(DS_GM_LINEAR_DATA, 0x80500008 + > > i, DS_GM_SIZE32, Data, 8192); > > memcpy(m_YUVData.Y + i, Data, 32768); > > } > > //Not an even number of 32768 byte chunks... > > if (i - FrameSize != 0) { > > //i -= 32768; > > g_DSP.GetMem(DS_GM_LINEAR_DATA, 0x80500008 + > > i, DS_GM_SIZE32, Data, (FrameSize > > - i) / 4); > > memcpy(m_YUVData.Y + i, Data, (FrameSize - > > i)); > > } > > > > //Read Cb data > > for (i=0; i<=FrameSize / 4-32768; i+2768) { > > g_DSP.GetMem(DS_GM_LINEAR_DATA, 0x80500008 + > > FrameSize + i, DS_GM_SIZE32, Data, > > 8192); > > memcpy(m_YUVData.Cb + i, Data, 32768); > > } > > //Not an even number of 32768 byte chunks... > > if (i - FrameSize / 4 != 0) { > > //i -= 32768; > > g_DSP.GetMem(DS_GM_LINEAR_DATA, 0x80500008 + > > FrameSize + i, DS_GM_SIZE32, Data, > > (FrameSize / 4 - i) / 4); > > memcpy(m_YUVData.Cb + i, Data, (FrameSize / 4 > > - i)); > > } > > > > //Read Cr Data > > for (i=0; i<=FrameSize / 4-32768; i+2768) { > > g_DSP.GetMem(DS_GM_LINEAR_DATA, 0x80500008 + > > FrameSize * 5 / 4 + i, > > DS_GM_SIZE32, Data, 8192); > > memcpy(m_YUVData.Cr + i, Data, 32768); > > } > > //Not an even number of 32768 byte chunks... > > if (i - FrameSize / 4 != 0) { > > //i -= 32768; > > g_DSP.GetMem(DS_GM_LINEAR_DATA, 0x80500008 + > > FrameSize * 5 / 4 + i, > > DS_GM_SIZE32, Data, (FrameSize / 4 - i) / 4); > > memcpy(m_YUVData.Cr + i, Data, (FrameSize / 4 > > - i)); > > } > > > > //Save to file if we have a file pointer > > if (pFile) > > { > > fwrite(m_YUVData.Y, FrameSize, 1, pFile); > > fwrite(m_YUVData.Cb, FrameSize / 4, 1, pFile); > > fwrite(m_YUVData.Cr, FrameSize / 4, 1, pFile); > > } > > > > //Set current frame data > > m_YUV.SetFrame(m_YUVData); > > > > //Force view to refresh > > ((CFrameWnd *)::AfxGetM |
Reply by ●May 25, 20042004-05-25
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TV will accept raw YUV format and hence you do not need colour space conversion. Also colour space conversion may be available as a ready made function as part of IMGLIB. Regds JS -----Original Message----- From: piyush kaul [mailto:] Sent: Monday, May 24, 2004 5:39 AM To: Jeff Brower Cc: Subject: Re: [c6x] YUV format for Video Driver in DM642 Hi Jeff, Thanks for the help. However I intend to use the EVM as a standalone system(unconnected to PC) and hence using any software like DirectDSP is out of question. Also the objective is to display real-time video through the video port on a Television or VGA Monitor and not through PC. Hence the code might not be relevent to my need as of now. I already have a reasonable implementation of real-time video display for VGA. However, as I communicated, I am not able to do without color-space conversion (YUV to RGB). As you might know, color-space conversion is highly intensive especially for large resolutions, hence my question whether it could be avoided. Sankaran suggests that it can not be avoided for VGA, hence I need to go with it atleast for VGA. Now need to look for TV. Regards Piyush --- Jeff Brower <> wrote: > Piyush- > > > I have been trying to display decoded video using > the > > DDK libraries on DM642. The output of the decoder > is > > YUV 4:2:0 format. However for displaying it > correctly > > on the VGA Monitor, I need to convert it to RGB > for > > proper color. The documentation seems to suggest > that > > feeding the YUV directly should also work but the > > color is not correct when I directly feed yuv > data. > > > > Even the example program which uses YUV for XGA > > displays incorrect colors. > > > > My guess is that the yuv works only for SDTV and > for > > monitors Color space conversion in software is > > required. > > Any experiences/hints would be very valueble. > > Below is some example source code that uses > DirectDSP software and reads MPEG4 > algorithm output from the DSK C6711 + IDK board > combination. The MPEG4 algorithm is > from Mecoso; this example shows D1 resolution about > 12 frame/sec on the DSK board > (relatively slow at 150 MHz). > > The GetMem() calls are DirectDSP API calls (actually > a C++ class on top of the > standard DSGetMem API call). Note the memcpy()'s to > grab separate Y, Cb, Cr format > data from DSP mem. Then there is a bunch more code > (SetFrame call) to convert YCbCr > data to RGB format suitable for display in a Win > bitmap -- but I did not post that > code. > > I hope this is helpful. > > -Jeff > > while (!g_DSP.GetFrameReady()); > > //Capture data and set current frame data > > //All sizes divided by four because we're reading > 4-byte chunks > //NOTE: Max read is 32768 bytes > > //Read Y data > for (i=0; i<FrameSize-32768; i+2768) { > g_DSP.GetMem(DS_GM_LINEAR_DATA, 0x80500008 + > i, DS_GM_SIZE32, Data, 8192); > memcpy(m_YUVData.Y + i, Data, 32768); > } > //Not an even number of 32768 byte chunks... > if (i - FrameSize != 0) { > //i -= 32768; > g_DSP.GetMem(DS_GM_LINEAR_DATA, 0x80500008 + > i, DS_GM_SIZE32, Data, (FrameSize > - i) / 4); > memcpy(m_YUVData.Y + i, Data, (FrameSize - > i)); > } > > //Read Cb data > for (i=0; i<=FrameSize / 4-32768; i+2768) { > g_DSP.GetMem(DS_GM_LINEAR_DATA, 0x80500008 + > FrameSize + i, DS_GM_SIZE32, Data, > 8192); > memcpy(m_YUVData.Cb + i, Data, 32768); > } > //Not an even number of 32768 byte chunks... > if (i - FrameSize / 4 != 0) { > //i -= 32768; > g_DSP.GetMem(DS_GM_LINEAR_DATA, 0x80500008 + > FrameSize + i, DS_GM_SIZE32, Data, > (FrameSize / 4 - i) / 4); > memcpy(m_YUVData.Cb + i, Data, (FrameSize / 4 > - i)); > } > > //Read Cr Data > for (i=0; i<=FrameSize / 4-32768; i+2768) { > g_DSP.GetMem(DS_GM_LINEAR_DATA, 0x80500008 + > FrameSize * 5 / 4 + i, > DS_GM_SIZE32, Data, 8192); > memcpy(m_YUVData.Cr + i, Data, 32768); > } > //Not an even number of 32768 byte chunks... > if (i - FrameSize / 4 != 0) { > //i -= 32768; > g_DSP.GetMem(DS_GM_LINEAR_DATA, 0x80500008 + > FrameSize * 5 / 4 + i, > DS_GM_SIZE32, Data, (FrameSize / 4 - i) / 4); > memcpy(m_YUVData.Cr + i, Data, (FrameSize / 4 > - i)); > } > > //Save to file if we have a file pointer > if (pFile) > { > fwrite(m_YUVData.Y, FrameSize, 1, pFile); > fwrite(m_YUVData.Cb, FrameSize / 4, 1, pFile); > fwrite(m_YUVData.Cr, FrameSize / 4, 1, pFile); > } > > //Set current frame data > m_YUV.SetFrame(m_YUVData); > > //Force view to refresh > ((CFrameWnd *)::AfxGetM > _____________________________________ > Note: If you do a simple "reply" with your email > client, only the author of this message will receive > your answer. You need to do a "reply all" if you > want your answer to be distributed to the entire > group. > > _____________________________________ > About this discussion group: > > To Join: Send an email to > To Post: Send an email to > > To Leave: Send an email to > Archives: http://www.yahoogroups.com/group/c6x > > Other Groups: http://www.dsprelated.com > > Yahoo! Groups Links > ===== ************************************** And---"A blind Understanding!" Heav'n replied. Piyush Kaul http://www.geocities.com/piyushkaul __________________________________ _____________________________________ Note: If you do a simple "reply" with your email client, only the author of this message will receive your answer. You need to do a "reply all" if you want your answer to be distributed to the entire group. _____________________________________ About this discussion group: To Join: Send an email to To Post: Send an email to To Leave: Send an email to Archives: http://www.yahoogroups.com/group/c6x Other Groups: http://www.dsprelated.com Yahoo! Groups Links |
