ffmpeg | branch: master | Thomas Volkert <tho...@homer-conferencing.com> | Sat Dec 6 19:54:07 2014 +0100| [a505c0d7373336a4cc5aa2022111c46bdd388b1f] | committer: Martin Storsjö
rtp: Initial H.261 support The packetizer only supports splitting at GOB headers - if such aren't available frequently enough, it splits at any random byte offset (not at a macroblock boundary either, which would be allowed by the spec) and sends a payload header pretend that it starts with a GOB header. As long as a receiver doesn't try to handle such cases cleverly but just drops broken frames, this shouldn't matter too much in practice. Signed-off-by: Martin Storsjö <mar...@martin.st> > http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=a505c0d7373336a4cc5aa2022111c46bdd388b1f --- Changelog | 1 + libavformat/Makefile | 2 + libavformat/rtpdec.c | 1 + libavformat/rtpdec_formats.h | 1 + libavformat/rtpdec_h261.c | 202 ++++++++++++++++++++++++++++++++++++++++++ libavformat/rtpenc.c | 19 +++- libavformat/rtpenc.h | 1 + libavformat/rtpenc_h261.c | 102 +++++++++++++++++++++ libavformat/sdp.c | 14 +++ libavformat/version.h | 4 +- 10 files changed, 343 insertions(+), 4 deletions(-) diff --git a/Changelog b/Changelog index 6af2e8a..85fb678 100644 --- a/Changelog +++ b/Changelog @@ -7,6 +7,7 @@ version <next>: - avplay now exits by default at the end of playback - XCB-based screen-grabber - creating DASH compatible fragmented MP4, MPEG-DASH segmenting muxer +- H.261 RTP payload format (RFC 4587) depacketizer and experimental packetizer version 11: diff --git a/libavformat/Makefile b/libavformat/Makefile index 035eb72..affb95a 100644 --- a/libavformat/Makefile +++ b/libavformat/Makefile @@ -32,6 +32,7 @@ OBJS-$(CONFIG_RTPDEC) += rdt.o \ rtpdec_amr.o \ rtpdec_asf.o \ rtpdec_g726.o \ + rtpdec_h261.o \ rtpdec_h263.o \ rtpdec_h263_rfc2190.o \ rtpdec_h264.o \ @@ -290,6 +291,7 @@ OBJS-$(CONFIG_RTP_MUXER) += rtp.o \ rtpenc_aac.o \ rtpenc_latm.o \ rtpenc_amr.o \ + rtpenc_h261.o \ rtpenc_h263.o \ rtpenc_h263_rfc2190.o \ rtpenc_hevc.o \ diff --git a/libavformat/rtpdec.c b/libavformat/rtpdec.c index b5e5200..97f1428 100644 --- a/libavformat/rtpdec.c +++ b/libavformat/rtpdec.c @@ -66,6 +66,7 @@ void ff_register_rtp_dynamic_payload_handlers(void) ff_register_dynamic_payload_handler(&ff_g726_24_dynamic_handler); ff_register_dynamic_payload_handler(&ff_g726_32_dynamic_handler); ff_register_dynamic_payload_handler(&ff_g726_40_dynamic_handler); + ff_register_dynamic_payload_handler(&ff_h261_dynamic_handler); ff_register_dynamic_payload_handler(&ff_h263_1998_dynamic_handler); ff_register_dynamic_payload_handler(&ff_h263_2000_dynamic_handler); ff_register_dynamic_payload_handler(&ff_h263_rfc2190_dynamic_handler); diff --git a/libavformat/rtpdec_formats.h b/libavformat/rtpdec_formats.h index 02335ed..0c9f49c 100644 --- a/libavformat/rtpdec_formats.h +++ b/libavformat/rtpdec_formats.h @@ -41,6 +41,7 @@ extern RTPDynamicProtocolHandler ff_g726_16_dynamic_handler; extern RTPDynamicProtocolHandler ff_g726_24_dynamic_handler; extern RTPDynamicProtocolHandler ff_g726_32_dynamic_handler; extern RTPDynamicProtocolHandler ff_g726_40_dynamic_handler; +extern RTPDynamicProtocolHandler ff_h261_dynamic_handler; extern RTPDynamicProtocolHandler ff_h263_1998_dynamic_handler; extern RTPDynamicProtocolHandler ff_h263_2000_dynamic_handler; extern RTPDynamicProtocolHandler ff_h263_rfc2190_dynamic_handler; diff --git a/libavformat/rtpdec_h261.c b/libavformat/rtpdec_h261.c new file mode 100644 index 0000000..4988300 --- /dev/null +++ b/libavformat/rtpdec_h261.c @@ -0,0 +1,202 @@ +/* + * RTP parser for H.261 payload format (RFC 4587) + * Copyright (c) 2014 Thomas Volkert <tho...@homer-conferencing.com> + * + * 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 "libavcodec/get_bits.h" +#include "avformat.h" +#include "rtpdec_formats.h" + +#define RTP_H261_PAYLOAD_HEADER_SIZE 4 + +struct PayloadContext { + AVIOContext *buf; + uint8_t endbyte; + int endbyte_bits; + uint32_t timestamp; +}; + +static av_cold PayloadContext *h261_new_context(void) +{ + return av_mallocz(sizeof(PayloadContext)); +} + +static void h261_free_dyn_buffer(AVIOContext **dyn_buf) +{ + uint8_t *ptr_dyn_buffer; + avio_close_dyn_buf(*dyn_buf, &ptr_dyn_buffer); + av_free(ptr_dyn_buffer); + *dyn_buf = NULL; +} + +static av_cold void h261_free_context(PayloadContext *pl_ctx) +{ + /* return if context is invalid */ + if (!pl_ctx) + return; + + /* free buffer if it is valid */ + if (pl_ctx->buf) { + h261_free_dyn_buffer(&pl_ctx->buf); + } + + /* free context */ + av_free(pl_ctx); +} + +static av_cold int h261_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 h261_handle_packet(AVFormatContext *ctx, PayloadContext *rtp_h261_ctx, + AVStream *st, AVPacket *pkt, uint32_t *timestamp, + const uint8_t *buf, int len, uint16_t seq, + int flags) +{ + int sbit, ebit, gobn, mbap, quant; + int res; + + /* drop data of previous packets in case of non-continuous (lossy) packet stream */ + if (rtp_h261_ctx->buf && rtp_h261_ctx->timestamp != *timestamp) { + h261_free_dyn_buffer(&rtp_h261_ctx->buf); + rtp_h261_ctx->endbyte_bits = 0; + } + + /* sanity check for size of input packet: 1 byte payload at least */ + if (len < RTP_H261_PAYLOAD_HEADER_SIZE + 1) { + av_log(ctx, AV_LOG_ERROR, "Too short RTP/H.261 packet, got %d bytes\n", len); + return AVERROR_INVALIDDATA; + } + + /* + * decode the H.261 payload header according to section 4.1 of RFC 4587: + * (uses 4 bytes between RTP header and H.261 stream per packet) + * + * 0 1 2 3 + * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 + * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + * |SBIT |EBIT |I|V| GOBN | MBAP | QUANT | HMVD | VMVD | + * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + * + * Start bit position (SBIT): 3 bits + * End bit position (EBIT): 3 bits + * INTRA-frame encoded data (I): 1 bit + * Motion Vector flag (V): 1 bit + * GOB number (GOBN): 4 bits + * Macroblock address predictor (MBAP): 5 bits + * Quantizer (QUANT): 5 bits + * Horizontal motion vector data (HMVD): 5 bits + * Vertical motion vector data (VMVD): 5 bits + */ + sbit = (buf[0] >> 5) & 0x07; + ebit = (buf[0] >> 2) & 0x07; + gobn = (buf[1] >> 4) & 0x0f; + mbap = ((buf[1] << 1) & 0x1e) | ((buf[2] >> 7) & 0x01); + quant = (buf[2] >> 2) & 0x1f; + + /* pass the H.261 payload header and continue with the actual payload */ + buf += RTP_H261_PAYLOAD_HEADER_SIZE; + len -= RTP_H261_PAYLOAD_HEADER_SIZE; + + /* start frame buffering with new dynamic buffer */ + if (!rtp_h261_ctx->buf) { + /* sanity check: a new frame starts with gobn=0, sbit=0, mbap=0, quant=0 */ + if (!gobn && !sbit && !mbap && !quant) { + res = avio_open_dyn_buf(&rtp_h261_ctx->buf); + if (res < 0) + return res; + /* update the timestamp in the frame packet with the one from the RTP packet */ + rtp_h261_ctx->timestamp = *timestamp; + } else { + /* frame not started yet, need more packets */ + return AVERROR(EAGAIN); + } + } + + /* do the "byte merging" at the boundaries of two consecutive frame fragments */ + if (rtp_h261_ctx->endbyte_bits || sbit) { + if (rtp_h261_ctx->endbyte_bits == sbit) { + rtp_h261_ctx->endbyte |= buf[0] & (0xff >> sbit); + rtp_h261_ctx->endbyte_bits = 0; + buf++; + len--; + avio_w8(rtp_h261_ctx->buf, rtp_h261_ctx->endbyte); + } else { + /* ebit/sbit values inconsistent, assuming packet loss */ + GetBitContext gb; + init_get_bits(&gb, buf, len*8 - ebit); + skip_bits(&gb, sbit); + if (rtp_h261_ctx->endbyte_bits) { + rtp_h261_ctx->endbyte |= get_bits(&gb, 8 - rtp_h261_ctx->endbyte_bits); + avio_w8(rtp_h261_ctx->buf, rtp_h261_ctx->endbyte); + } + while (get_bits_left(&gb) >= 8) + avio_w8(rtp_h261_ctx->buf, get_bits(&gb, 8)); + rtp_h261_ctx->endbyte_bits = get_bits_left(&gb); + if (rtp_h261_ctx->endbyte_bits) + rtp_h261_ctx->endbyte = get_bits(&gb, rtp_h261_ctx->endbyte_bits) << + (8 - rtp_h261_ctx->endbyte_bits); + ebit = 0; + len = 0; + } + } + if (ebit) { + if (len > 0) + avio_write(rtp_h261_ctx->buf, buf, len - 1); + rtp_h261_ctx->endbyte_bits = 8 - ebit; + rtp_h261_ctx->endbyte = buf[len - 1] & (0xff << ebit); + } else { + avio_write(rtp_h261_ctx->buf, buf, len); + } + + /* RTP marker bit means: last fragment of current frame was received; + otherwise, an additional fragment is needed for the current frame */ + if (!(flags & RTP_FLAG_MARKER)) + return AVERROR(EAGAIN); + + /* write the completed last byte from the "byte merging" */ + if (rtp_h261_ctx->endbyte_bits) + avio_w8(rtp_h261_ctx->buf, rtp_h261_ctx->endbyte); + rtp_h261_ctx->endbyte_bits = 0; + + /* close frame buffering and create resulting A/V packet */ + res = ff_rtp_finalize_packet(pkt, &rtp_h261_ctx->buf, st->index); + if (res < 0) + return res; + + return 0; +} + +RTPDynamicProtocolHandler ff_h261_dynamic_handler = { + .enc_name = "H261", + .codec_type = AVMEDIA_TYPE_VIDEO, + .codec_id = AV_CODEC_ID_H261, + .init = h261_init, + .alloc = h261_new_context, + .free = h261_free_context, + .parse_packet = h261_handle_packet, + .static_payload_id = 31, +}; diff --git a/libavformat/rtpenc.c b/libavformat/rtpenc.c index e5dc805..bf82da0 100644 --- a/libavformat/rtpenc.c +++ b/libavformat/rtpenc.c @@ -49,6 +49,7 @@ static const AVClass rtp_muxer_class = { static int is_supported(enum AVCodecID id) { switch(id) { + case AV_CODEC_ID_H261: case AV_CODEC_ID_H263: case AV_CODEC_ID_H263P: case AV_CODEC_ID_H264: @@ -88,7 +89,7 @@ static int is_supported(enum AVCodecID id) static int rtp_write_header(AVFormatContext *s1) { RTPMuxContext *s = s1->priv_data; - int n; + int n, ret = AVERROR(EINVAL); AVStream *st; if (s1->nb_streams != 1) { @@ -191,6 +192,17 @@ static int rtp_write_header(AVFormatContext *s1) s->max_payload_size = n * TS_PACKET_SIZE; s->buf_ptr = s->buf; break; + case AV_CODEC_ID_H261: + if (s1->strict_std_compliance > FF_COMPLIANCE_EXPERIMENTAL) { + av_log(s, AV_LOG_ERROR, + "Packetizing H261 is experimental and produces incorrect " + "packetization for cases where GOBs don't fit into packets " + "(even though most receivers may handle it just fine). " + "Please set -f_strict experimental in order to enable it.\n"); + ret = AVERROR_EXPERIMENTAL; + goto fail; + } + break; case AV_CODEC_ID_H264: /* check for H.264 MP4 syntax */ if (st->codec->extradata_size > 4 && st->codec->extradata[0] == 1) { @@ -273,7 +285,7 @@ defaultcase: fail: av_freep(&s->buf); - return AVERROR(EINVAL); + return ret; } /* send an rtcp sender report packet */ @@ -567,6 +579,9 @@ static int rtp_write_packet(AVFormatContext *s1, AVPacket *pkt) case AV_CODEC_ID_H264: ff_rtp_send_h264(s1, pkt->data, size); break; + case AV_CODEC_ID_H261: + ff_rtp_send_h261(s1, pkt->data, size); + break; case AV_CODEC_ID_H263: if (s->flags & FF_RTP_FLAG_RFC2190) { int mb_info_size = 0; diff --git a/libavformat/rtpenc.h b/libavformat/rtpenc.h index 4a72a49..f2ac0fa 100644 --- a/libavformat/rtpenc.h +++ b/libavformat/rtpenc.h @@ -81,6 +81,7 @@ typedef struct RTPMuxContext RTPMuxContext; void ff_rtp_send_data(AVFormatContext *s1, const uint8_t *buf1, int len, int m); void ff_rtp_send_h264(AVFormatContext *s1, const uint8_t *buf1, int size); +void ff_rtp_send_h261(AVFormatContext *s1, const uint8_t *buf1, int size); void ff_rtp_send_h263(AVFormatContext *s1, const uint8_t *buf1, int size); void ff_rtp_send_h263_rfc2190(AVFormatContext *s1, const uint8_t *buf1, int size, const uint8_t *mb_info, int mb_info_size); diff --git a/libavformat/rtpenc_h261.c b/libavformat/rtpenc_h261.c new file mode 100644 index 0000000..514e7bf --- /dev/null +++ b/libavformat/rtpenc_h261.c @@ -0,0 +1,102 @@ +/* + * RTP packetization for H.261 video (RFC 4587) + * Copyright (c) 2014 Thomas Volkert <tho...@homer-conferencing.com> + * + * 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 "rtpenc.h" + +#define RTP_H261_HEADER_SIZE 4 + +static const uint8_t *find_resync_marker_reverse(const uint8_t *restrict start, + const uint8_t *restrict end) +{ + const uint8_t *p = end - 1; + start += 1; /* Make sure we never return the original start. */ + for (; p > start; p--) { + if (p[0] == 0 && p[1] == 1) + return p; + } + return end; +} + +void ff_rtp_send_h261(AVFormatContext *ctx, const uint8_t *frame_buf, int frame_size) +{ + int cur_frame_size; + int last_packet_of_frame; + RTPMuxContext *rtp_ctx = ctx->priv_data; + + /* use the default 90 KHz time stamp */ + rtp_ctx->timestamp = rtp_ctx->cur_timestamp; + + /* continue as long as not all frame data is processed */ + while (frame_size > 0) { + /* + * encode the H.261 payload header according to section 4.1 of RFC 4587: + * (uses 4 bytes between RTP header and H.261 stream per packet) + * + * 0 1 2 3 + * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 + * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + * |SBIT |EBIT |I|V| GOBN | MBAP | QUANT | HMVD | VMVD | + * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + * + * Start bit position (SBIT): 3 bits + * End bit position (EBIT): 3 bits + * INTRA-frame encoded data (I): 1 bit + * Motion Vector flag (V): 1 bit + * GOB number (GOBN): 4 bits + * Macroblock address predictor (MBAP): 5 bits + * Quantizer (QUANT): 5 bits + * Horizontal motion vector data (HMVD): 5 bits + * Vertical motion vector data (VMVD): 5 bits + */ + rtp_ctx->buf[0] = 1; /* sbit=0, ebit=0, i=0, v=1 */ + rtp_ctx->buf[1] = 0; /* gobn=0, mbap=0 */ + rtp_ctx->buf[2] = 0; /* quant=0, hmvd=5 */ + rtp_ctx->buf[3] = 0; /* vmvd=0 */ + if (frame_size < 2 || frame_buf[0] != 0 || frame_buf[1] != 1) { + /* A full, correct fix for this would be to make the H261 encoder + * support inserting extra GOB headers (triggered by setting e.g. + * "-ps 1"), and including information about macroblock boundaries + * (such as for h263_rfc2190). */ + av_log(ctx, AV_LOG_WARNING, + "RTP/H261 packet not cut at a GOB boundary, not signaled correctly\n"); + } + + cur_frame_size = FFMIN(rtp_ctx->max_payload_size - RTP_H261_HEADER_SIZE, frame_size); + + /* look for a better place to split the frame into packets */ + if (cur_frame_size < frame_size) { + const uint8_t *packet_end = find_resync_marker_reverse(frame_buf, + frame_buf + cur_frame_size); + cur_frame_size = packet_end - frame_buf; + } + + /* calculate the "marker" bit for the RTP header */ + last_packet_of_frame = cur_frame_size == frame_size; + + /* complete and send RTP packet */ + memcpy(&rtp_ctx->buf[RTP_H261_HEADER_SIZE], frame_buf, cur_frame_size); + ff_rtp_send_data(ctx, rtp_ctx->buf, RTP_H261_HEADER_SIZE + cur_frame_size, last_packet_of_frame); + + frame_buf += cur_frame_size; + frame_size -= cur_frame_size; + } +} diff --git a/libavformat/sdp.c b/libavformat/sdp.c index a14a239..fe43e04 100644 --- a/libavformat/sdp.c +++ b/libavformat/sdp.c @@ -498,6 +498,20 @@ static char *sdp_write_media_attributes(char *buff, int size, AVCodecContext *c, payload_type, mode, config ? config : ""); break; } + case AV_CODEC_ID_H261: + { + const char *pic_fmt = NULL; + /* only QCIF and CIF are specified as supported in RFC 4587 */ + if (c->width == 176 && c->height == 144) + pic_fmt = "QCIF=1"; + else if (c->width == 352 && c->height == 288) + pic_fmt = "CIF=1"; + if (payload_type >= RTP_PT_PRIVATE) + av_strlcatf(buff, size, "a=rtpmap:%d H261/90000\r\n", payload_type); + if (pic_fmt) + av_strlcatf(buff, size, "a=fmtp:%d %s\r\n", payload_type, pic_fmt); + break; + } case AV_CODEC_ID_H263: case AV_CODEC_ID_H263P: /* a=framesize is required by 3GPP TS 26.234 (PSS). It diff --git a/libavformat/version.h b/libavformat/version.h index 16c5e2e..b2f5327 100644 --- a/libavformat/version.h +++ b/libavformat/version.h @@ -30,8 +30,8 @@ #include "libavutil/version.h" #define LIBAVFORMAT_VERSION_MAJOR 56 -#define LIBAVFORMAT_VERSION_MINOR 7 -#define LIBAVFORMAT_VERSION_MICRO 2 +#define LIBAVFORMAT_VERSION_MINOR 8 +#define LIBAVFORMAT_VERSION_MICRO 0 #define LIBAVFORMAT_VERSION_INT AV_VERSION_INT(LIBAVFORMAT_VERSION_MAJOR, \ LIBAVFORMAT_VERSION_MINOR, \ _______________________________________________ ffmpeg-cvslog mailing list ffmpeg-cvslog@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-cvslog
