search for: ogg_packet

...f using the ogg python bindings to do pure ogg container encoding. I started looking at the libogg in the hopes of retooling the bindings to follow a better object model and it actually looks like the problem is down in libogg, not the bindings. Am I crazy or does libogg rely on libvorbis to return ogg_packets, and that there are no functions that will build an ogg_packet for you from your own data like an array of bytes? It looks like API users are required to fill in all the meta fields of the ogg_packet themselves? Is this correct? -------------- next part -------------- An HTML attachment was scrubb...

Can I join many ogg_packet together and decode it to PCM? Or I have to encode each ogg_packet at a time? If each packet is 1024 long, can I join 1.5 of packet (1024+512), and decode that 1024+512 packet, and then decode the 512 left? Or I must decode a whole packet, and can't cut it or decode only some of it (not a...

Hi While implementing OSS Ogg/Vorbis encoding and streaming using RTP/RTCP for both unicast and multicast, I have come across a few issues I need to clear out regarding the numbering of ogg_packets and their granulepos value. Below are the result for two different scenarios. <p>In the first scenario, ogg_packets are generated using a) vorbis_analysis_headerout() b) while true vorbis_analysis_buffer() vorbis_analysis_wrote() c)...

Happy new millenium! Summary: I'm having a problem queueing up the ogg_packet results of vorbis_analyze() for later writing to an .ogg stream. The docs don't seem to say if this is permissable or not. Hence, I don't know if I'm using the API incorrectly, or if this is an actual bug. ----- Attached is a short patch to vorbis-tools/oggenc/encode.c (from CVS hea...

...format has a RTP packetizer that works for both Vorbis and Theora, implemented in rtpenc_xiph.c. But this packetizer is meant for use in the RTP muxer of libavformat itself, and the RTP muxer relies on the packet's metadata, that, when it comes from libvorbis, is derived from the fields of the ogg_packet structure. Thus, you still need that ogg_packet structure anyway. Regards, -- Nicolas George

hi, in my quest to grok ogg i tried to write a small program which extracts ogg_packets, and stuffs them back into ogg pages (which are then written to a file). extracting the packets works fine, but i have problems stuffing them into a new ogg stream. pseudo code: ogg_stream_init(os, serialno) foreach p in packets: ogg_stream_packetin(os, p) // try to extract a page...

...uster has the exact same timecode). 2. FFmpeg seems to use granulepos for presentation timestamp - is this correct? See here: https://github.com/FFmpeg/FFmpeg/blob/master/libavcodec/libvorbisenc.c#L345l To me it seems the breakdown of ffmpeg's libvorbis_encode_frame is: - get an ogg_packet from libvorbis (I think this contains a *single* vorbis block, right?) - store just the data from that packet (no header) in ffmpeg's own AVPacket struct - eventually this AVPacket data will be inserted as the contents of a WebM (Matroska) block: https://github.com/FFmpeg/FFm...

...MP4 save routine b) submit ogg packet header_comment (header and data) to MP4 save routine c) submit ogg packet header_code (header and data) to MP4 save routine d) Get Ogg page(s) containing the header, comment and code using ogg_stream_flush and save it into an .ogg file Note that the ogg_packets and not the ogg page is submitted to the MP4 save routine. Then I do a) If we have a block ready, then get next ogg_packet with vorbis_bitrate_flushpacket b) If we didn't get an ogg packet or if we don't have a block then b1) get a block with vorbis_analysis_blockout b...

Hi. I am trying to implement an ogg codec using libogg, and testing with a piece of encoded data you can see below. It consists of 4 pages, the first two being header data, the third containing two packets of data and the last containing one packet of data. I am confused at the results I get if I corrupt the third page (The first one of the two that contain data). If I corrupt the first page,

...red to make ogg_page work? // FIXME: Why is there no ogg_page_create? ogg_page og_allocated = {0, 0, 0, 0}; ogg_page* og = &og_allocated; // Stream data structures ogg_stream_state *os = NULL; // FIXME: Why is this magic required to make ogg_page work? // FIXME: Why is there no ogg_packet_create? ogg_packet op_allocated = {0, 0, 0, 0, 0, 0}; ogg_packet* op = &op_allocated; // Ogg init oy = ogg_sync_create(); // Stream init // Need to set the serial number later os = ogg_stream_create(-1); // CAUTION: Just about anything you do wrong pops a bus error. // Y...

...> 2. FFmpeg seems to use granulepos for presentation timestamp - is this > correct? See here: > > https://github.com/FFmpeg/FFmpeg/blob/master/libavcodec/libvorbisenc.c#L345l > > To me it seems the breakdown of ffmpeg's libvorbis_encode_frame is: > > - get an ogg_packet from libvorbis (I think this contains a *single* > vorbis block, right?) > - store just the data from that packet (no header) in ffmpeg's own > AVPacket struct > - eventually this AVPacket data will be inserted as the contents of a > WebM (Matroska) block: > &gt...

1.) after initializing a ogg_stream_state may I just keep calling ogg_stream_packetin with valid ogg_packet's until no more ogg_packets needs to be added? Or do I need to call ogg_stream_pageout after every ogg_stream_packetin? Iaw may I delay calling ogg_stream_pageout until there are no more packets to be added? 2.) I assume I have call ogg_stream_pageout until no more pages can be created and...

...rame, send it over the network and decode it on "the other side". For now, it must only work locally so we don't care about the transmission. This is what I've understood till now: I have a char * buffer from the camera RG24,I convert it to YCbCr 4:4:4, I encode it, resulting an ogg_packet. Then I provide this ogg_packet to the decoder, get the YCbCr buffer , convert it back to RGB24 then display it. Now the questions: I have a Codec class with a function encoderInitialize(), where I initialize the encoder, filling a th_info structure with the image's properties, fps, aspect...

L'octidi 18 pluviôse, an CCXXV, Miscellaneous a écrit : > I've built some simple code on the excellent libvorbis API overview on > the xiph.org site, but the example relies on the ogg_packet struct for > final output and input to decoder, and shows now examples on how to do > without it. Why do you not want it? It is just a simple C struct to carry the packet's metadata. > oggpack_buffer comes from ogg/ogg.h, so I guess it may add some things > not native to "pur...

...----------------------------------------- /static long serialno; static ogg_int64_t granulepos = 0; static ogg_int64_t packetno = 0;/ ------------------------------------------------------------------------------------------------ /static int oggzHungry(OGGZ * oggz, int empty, void * user_data) { ogg_packet op; //unsigned char buf[1]; //buf[0] = 'A' + (int)packetno; unsigned char buf[2]; buf[0] = 0; buf[1] = 0; memset(&op, 0, sizeof(ogg_packet)); op.packet = buf; op.bytes = 2; //op.bytes = 1; op.granulepos = granulepos; op.packetno = packetno; if (packetno == 0) o...

Hi, I am actually working on a c++ wrapper for ogg/theora. It will be a small library to easily create command line tools to cut/cat video-files and to extract and join the video and audio stream etc. However, I started the project and found some very strange behaviors: I stored some ogg_packet objects (which are created on the heap) in a list. When I make several calls to ogg_stream_pagein() and ogg_stream_packetout(), the packets are accidentally overwritten by some nonsense. I am not sure what really happens, but I guess the libogg writers wanted to reduce the memory copy to a minim...

Hi, Searched in Google, browsed xiph vorbis sites but found no good information about how to get the current playtime out of the granuleposition of the ogg_packet. Anyone knows if there is any 'Programming with libvorbis' documentation out there, cause on xiph's site (http://www.xiph.org/vorbis/doc/) there's nothing :( Any help? THX, Tom

I was wondering. When doing ogg only encoding, how do you mark end of stream? I am setting ogg_packet.e_o_s and then submitting it via ogg_stream_packetin() and then, because its the last potential page ogg_stream_flush()ing it. But when I walk through the file, EOS is not set on that logical bitstream. I have been using oggenc.c/encoder.c and oggdec.c/decoder.c for examples, but because the packet...

...know which page a packet started and ended on -- in particular, an application may want to cache the byte offset of the start of certain packets in order to more easily return to that position in the file later. As of liboggz 1.1.0, an OggzRead callback provides an oggz_packet: /** * An ogg_packet and its position in the stream. */ typedef struct { /** The ogg_packet structure, defined in <ogg/ogg.h> */ ogg_packet op; /** Its position */ oggz_position pos; } oggz_packet; Older applications will continue to work, casting this structure as an ogg_pa...

...er headerContent = { {'O', 'p', 'u', 's', 'H', 'e', 'a', 'd'}, 1, //Version 2, //Channels 0, //pre-skip 44100, //Original samplerate 0, //output gain 0}; //Mapping family ogg_packet header; header.packet = (unsigned char*)&headerContent; header.bytes = sizeof(struct OggHeader); header.b_o_s = 1; //Header must set beginning_of_stream header.e_o_s = 0; header.granulepos = -1; //This packet does not contain audio data, so granule-position = -1 header.p...