---------- Forwarded message ---------- From: rukhsana afroz <[email protected]> Date: Mon, Apr 4, 2011 at 8:41 PM Subject: Re: [FFmpeg-devel] GSoC project (JPEG 2000) To: FFmpeg development discussions and patches <[email protected]>
On Mon, Apr 4, 2011 at 8:08 PM, compn <[email protected]> wrote: > On Mon, 4 Apr 2011 19:35:12 -0700, rukhsana afroz wrote: > >On Tue, Mar 29, 2011 at 4:56 PM, Michael Niedermayer <[email protected] > >wrote: > >Most of the files fail when the decoder retrieves the coding style of the > >j2k file and gets the error "no extra cblk styles supported". The files in > >"testfiles_jp2" do not fail in this IF block. Actually coding style is > >retrieved at the beginning of decoding process, before entering to the > >actual codestream. I looked for exact rfc of jpeg2000 coding standard in > the > >internet, however did not find anything useful. Could you please refer me > >the standard rfc based on what this code has been developed? > > did you see this document already? > http://www.jpeg.org/public/fcd15444-1.pdf > > (linked to from http://wiki.multimedia.cx/index.php?title=JPEG_2000 ) > Thanks Compn. I got the partial of this document, not the full one. It seems, in the document, for J2K_SOD the marker is 0xff52, for J2K_COC marker is 0xff53, and for J2K_TLM marker is 0xff55. However in the code, marker 0xff55 has been assigned to all J2L_TLM, J2K_SOD and J2K_COC. switch(marker){ case J2K_SIZ: ret = get_siz(s); break; case J2K_COC: ret = get_coc(s, codsty, properties); break; case J2K_COD: ret = get_cod(s, codsty, properties); break; case J2K_QCC: ret = get_qcc(s, len, qntsty, properties); break; case J2K_QCD: ret = get_qcd(s, len, qntsty, properties); break; case J2K_SOT: if (!(ret = get_sot(s))){ codsty = s->tile[s->curtileno].codsty; qntsty = s->tile[s->curtileno].qntsty; properties = s->tile[s->curtileno].properties; } break; case J2K_COM: // the comment is ignored s->buf += len - 2; break; default: av_log(s->avctx, AV_LOG_ERROR, "unsupported marker 0x%.4X at pos 0x%x\n", marker, s->buf - s->buf_start - 4); s->buf += len - 2; break; } I believe, these portion of code need to be corrected. All markers (J2L_SOD, J2K_COC, J2L_TLM) need to be distinguished separately and their corresponding functions need to be implemented. I am trying myself to solve these bugs at this stage with less code. Thanks -- Rukhsana Ruby Phd Student Department of Electrical & Computer Engineering The University of British Columbia ============================ -- Rukhsana Ruby Phd Student Department of Electrical & Computer Engineering The University of British Columbia ============================
_______________________________________________ libav-devel mailing list [email protected] https://lists.libav.org/mailman/listinfo/libav-devel
