From 8992cb1d0d07edc33d274f6d7924ecdf6f83d994 Mon Sep 17 00:00:00 2001 From: Tim Redfern Date: Thu, 5 Sep 2013 17:57:22 +0100 Subject: making act segmenter --- ffmpeg/libavformat/rtpdec_h263_rfc2190.c | 214 +++++++++++++++++++++++++++++++ 1 file changed, 214 insertions(+) create mode 100644 ffmpeg/libavformat/rtpdec_h263_rfc2190.c (limited to 'ffmpeg/libavformat/rtpdec_h263_rfc2190.c') diff --git a/ffmpeg/libavformat/rtpdec_h263_rfc2190.c b/ffmpeg/libavformat/rtpdec_h263_rfc2190.c new file mode 100644 index 0000000..4b6e996 --- /dev/null +++ b/ffmpeg/libavformat/rtpdec_h263_rfc2190.c @@ -0,0 +1,214 @@ +/* + * RTP H.263 Depacketizer, RFC 2190 + * Copyright (c) 2012 Martin Storsjo + * Based on the GStreamer H.263 Depayloder: + * Copyright 2005 Wim Taymans + * Copyright 2007 Edward Hervey + * Copyright 2007 Nokia Corporation + * Copyright 2007 Collabora Ltd, Philippe Kalaf + * Copyright 2010 Mark Nauwelaerts + * + * This file is part of Libav. + * + * Libav is free software; you can redistribute it and/or + * modify it under the terms of the GNU Lesser General Public + * License as published by the Free Software Foundation; either + * version 2.1 of the License, or (at your option) any later version. + * + * Libav is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser General Public + * License along with Libav; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA + */ + +#include "avformat.h" +#include "rtpdec_formats.h" +#include "libavutil/intreadwrite.h" +#include "libavcodec/get_bits.h" + +struct PayloadContext { + AVIOContext *buf; + uint8_t endbyte; + int endbyte_bits; + uint32_t timestamp; + int newformat; +}; + +static PayloadContext *h263_new_context(void) +{ + return av_mallocz(sizeof(PayloadContext)); +} + +static void h263_free_context(PayloadContext *data) +{ + if (!data) + return; + if (data->buf) { + uint8_t *p; + avio_close_dyn_buf(data->buf, &p); + av_free(p); + } + av_free(data); +} + +static int h263_init(AVFormatContext *ctx, int st_index, PayloadContext *data) +{ + if (st_index < 0) + return 0; + ctx->streams[st_index]->need_parsing = AVSTREAM_PARSE_FULL; + return 0; +} + +static int h263_handle_packet(AVFormatContext *ctx, PayloadContext *data, + AVStream *st, AVPacket *pkt, uint32_t *timestamp, + const uint8_t *buf, int len, uint16_t seq, + int flags) +{ + /* Corresponding to header fields in the RFC */ + int f, p, i, sbit, ebit, src, r; + int header_size, ret; + + if (data->newformat) + return ff_h263_handle_packet(ctx, data, st, pkt, timestamp, buf, len, + seq, flags); + + if (data->buf && data->timestamp != *timestamp) { + /* Dropping old buffered, unfinished data */ + uint8_t *p; + avio_close_dyn_buf(data->buf, &p); + av_free(p); + data->buf = NULL; + } + + if (len < 4) { + av_log(ctx, AV_LOG_ERROR, "Too short H.263 RTP packet: %d\n", len); + return AVERROR_INVALIDDATA; + } + + f = buf[0] & 0x80; + p = buf[0] & 0x40; + if (!f) { + /* Mode A */ + header_size = 4; + i = buf[1] & 0x10; + r = ((buf[1] & 0x01) << 3) | ((buf[2] & 0xe0) >> 5); + } else if (!p) { + /* Mode B */ + header_size = 8; + if (len < header_size) { + av_log(ctx, AV_LOG_ERROR, + "Too short H.263 RTP packet: %d bytes, %d header bytes\n", + len, header_size); + return AVERROR_INVALIDDATA; + } + r = buf[3] & 0x03; + i = buf[4] & 0x80; + } else { + /* Mode C */ + header_size = 12; + if (len < header_size) { + av_log(ctx, AV_LOG_ERROR, + "Too short H.263 RTP packet: %d bytes, %d header bytes\n", + len, header_size); + return AVERROR_INVALIDDATA; + } + r = buf[3] & 0x03; + i = buf[4] & 0x80; + } + sbit = (buf[0] >> 3) & 0x7; + ebit = buf[0] & 0x7; + src = (buf[1] & 0xe0) >> 5; + if (!(buf[0] & 0xf8)) { /* Reserved bits in RFC 2429/4629 are zero */ + if ((src == 0 || src >= 6) && r) { + /* Invalid src for this format, and bits that should be zero + * according to RFC 2190 aren't zero. */ + av_log(ctx, AV_LOG_WARNING, + "Interpreting H263 RTP data as RFC 2429/4629 even though " + "signalled with a static payload type.\n"); + data->newformat = 1; + return ff_h263_handle_packet(ctx, data, st, pkt, timestamp, buf, + len, seq, flags); + } + } + + buf += header_size; + len -= header_size; + + if (!data->buf) { + /* Check the picture start code, only start buffering a new frame + * if this is correct */ + if (len > 4 && AV_RB32(buf) >> 10 == 0x20) { + ret = avio_open_dyn_buf(&data->buf); + if (ret < 0) + return ret; + data->timestamp = *timestamp; + } else { + /* Frame not started yet, skipping */ + return AVERROR(EAGAIN); + } + } + + if (data->endbyte_bits || sbit) { + if (data->endbyte_bits == sbit) { + data->endbyte |= buf[0] & (0xff >> sbit); + data->endbyte_bits = 0; + buf++; + len--; + avio_w8(data->buf, data->endbyte); + } else { + /* Start/end skip bits not matching - missed packets? */ + GetBitContext gb; + init_get_bits(&gb, buf, len*8 - ebit); + skip_bits(&gb, sbit); + if (data->endbyte_bits) { + data->endbyte |= get_bits(&gb, 8 - data->endbyte_bits); + avio_w8(data->buf, data->endbyte); + } + while (get_bits_left(&gb) >= 8) + avio_w8(data->buf, get_bits(&gb, 8)); + data->endbyte_bits = get_bits_left(&gb); + if (data->endbyte_bits) + data->endbyte = get_bits(&gb, data->endbyte_bits) << + (8 - data->endbyte_bits); + ebit = 0; + len = 0; + } + } + if (ebit) { + if (len > 0) + avio_write(data->buf, buf, len - 1); + data->endbyte_bits = 8 - ebit; + data->endbyte = buf[len - 1] & (0xff << ebit); + } else { + avio_write(data->buf, buf, len); + } + + if (!(flags & RTP_FLAG_MARKER)) + return AVERROR(EAGAIN); + + if (data->endbyte_bits) + avio_w8(data->buf, data->endbyte); + data->endbyte_bits = 0; + + ret = ff_rtp_finalize_packet(pkt, &data->buf, st->index); + if (ret < 0) + return ret; + if (!i) + pkt->flags |= AV_PKT_FLAG_KEY; + + return 0; +} + +RTPDynamicProtocolHandler ff_h263_rfc2190_dynamic_handler = { + .codec_type = AVMEDIA_TYPE_VIDEO, + .codec_id = AV_CODEC_ID_H263, + .init = h263_init, + .parse_packet = h263_handle_packet, + .alloc = h263_new_context, + .free = h263_free_context, + .static_payload_id = 34, +}; -- cgit v1.2.3