rtp: Packetization of JPEG (RFC 2435)

Changelog

@@ -48,6 +48,7 @@ version <next>:
 - Microsoft Screen 2 decoder
 - RTP depacketization of JPEG
 - Smooth Streaming live segmenter muxer
+- RTP packetization of JPEG
 
 
 version 0.8:

libavformat/Makefile

@@ -253,6 +253,7 @@ OBJS-$(CONFIG_RTP_MUXER)                 += rtp.o         \
                                             rtpenc_amr.o     \
                                             rtpenc_h263.o    \
                                             rtpenc_h263_rfc2190.o \
+                                            rtpenc_jpeg.o \
                                             rtpenc_mpv.o     \
                                             rtpenc.o      \
                                             rtpenc_h264.o \

libavformat/rtpenc.c

@@ -75,6 +75,7 @@ static int is_supported(enum AVCodecID id)
     case AV_CODEC_ID_ADPCM_G722:
     case AV_CODEC_ID_ADPCM_G726:
     case AV_CODEC_ID_ILBC:
+    case AV_CODEC_ID_MJPEG:
         return 1;
     default:
         return 0;
@@ -524,6 +525,9 @@ static int rtp_write_packet(AVFormatContext *s1, AVPacket *pkt)
     case AV_CODEC_ID_ILBC:
         rtp_send_ilbc(s1, pkt->data, size);
         break;
+    case AV_CODEC_ID_MJPEG:
+        ff_rtp_send_jpeg(s1, pkt->data, size);
+        break;
     default:
         /* better than nothing : send the codec raw data */
         rtp_send_raw(s1, pkt->data, size);

libavformat/rtpenc.h

@@ -87,6 +87,7 @@ void ff_rtp_send_amr(AVFormatContext *s1, const uint8_t *buff, int size);
 void ff_rtp_send_mpegvideo(AVFormatContext *s1, const uint8_t *buf1, int size);
 void ff_rtp_send_xiph(AVFormatContext *s1, const uint8_t *buff, int size);
 void ff_rtp_send_vp8(AVFormatContext *s1, const uint8_t *buff, int size);
+void ff_rtp_send_jpeg(AVFormatContext *s1, const uint8_t *buff, int size);
 
 const uint8_t *ff_h263_find_resync_marker_reverse(const uint8_t *restrict start,
                                                   const uint8_t *restrict end);

libavformat/rtpenc_jpeg.c

+/*
+ * RTP JPEG-compressed video Packetizer, RFC 2435
+ * Copyright (c) 2012 Samuel Pitoiset
+ *
+ * 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/bytestream.h"
+#include "libavcodec/mjpeg.h"
+#include "libavutil/intreadwrite.h"
+#include "rtpenc.h"
+
+void ff_rtp_send_jpeg(AVFormatContext *s1, const uint8_t *buf, int size)
+{
+    RTPMuxContext *s = s1->priv_data;
+    const uint8_t *qtables = NULL;
+    int nb_qtables = 0;
+    uint8_t type = 1; /* default pixel format is PIX_FMT_YUVJ420P */
+    uint8_t w, h;
+    uint8_t *p;
+    int off = 0; /* fragment offset of the current JPEG frame */
+    int len;
+    int i;
+
+    s->buf_ptr   = s->buf;
+    s->timestamp = s->cur_timestamp;
+
+    /* convert video pixel dimensions from pixels to blocks */
+    w = s1->streams[0]->codec->width  >> 3;
+    h = s1->streams[0]->codec->height >> 3;
+
+    /* check if pixel format is not the normal 420 case */
+    if (s1->streams[0]->codec->pix_fmt == PIX_FMT_YUVJ422P) {
+        type = 0;
+    } else if (s1->streams[0]->codec->pix_fmt == PIX_FMT_YUVJ420P) {
+        type = 1;
+    } else {
+        av_log(s1, AV_LOG_ERROR, "Unsupported pixel format\n");
+        return;
+    }
+
+    /* preparse the header for getting some infos */
+    for (i = 0; i < size; i++) {
+        if (buf[i] != 0xff)
+            continue;
+
+        if (buf[i + 1] == DQT) {
+            if (buf[i + 4])
+                av_log(s1, AV_LOG_WARNING,
+                       "Only 8-bit precision is supported.\n");
+
+            /* a quantization table is 64 bytes long */
+            nb_qtables = AV_RB16(&buf[i + 2]) / 65;
+            if (i + 4 + nb_qtables * 65 > size) {
+                av_log(s1, AV_LOG_ERROR, "Too short JPEG header. Aborted!\n");
+                return;
+            }
+
+            qtables = &buf[i + 4];
+        } else if (buf[i + 1] == SOF0) {
+            if (buf[i + 14] != 17 || buf[i + 17] != 17) {
+                av_log(s1, AV_LOG_ERROR,
+                       "Only 1x1 chroma blocks are supported. Aborted!\n");
+                return;
+            }
+        } else if (buf[i + 1] == SOS) {
+            /* SOS is last marker in the header */
+            i += AV_RB16(&buf[i + 2]) + 2;
+            break;
+        }
+    }
+
+    /* skip JPEG header */
+    buf  += i;
+    size -= i;
+
+    for (i = size - 2; i >= 0; i--) {
+        if (buf[i] == 0xff && buf[i + 1] == EOI) {
+            /* Remove the EOI marker */
+            size = i;
+            break;
+        }
+    }
+
+    p = s->buf_ptr;
+    while (size > 0) {
+        int hdr_size = 8;
+
+        if (off == 0 && nb_qtables)
+            hdr_size += 4 + 64 * nb_qtables;
+
+        /* payload max in one packet */
+        len = FFMIN(size, s->max_payload_size - hdr_size);
+
+        /* set main header */
+        bytestream_put_byte(&p, 0);
+        bytestream_put_be24(&p, off);
+        bytestream_put_byte(&p, type);
+        bytestream_put_byte(&p, 255);
+        bytestream_put_byte(&p, w);
+        bytestream_put_byte(&p, h);
+
+        if (off == 0 && nb_qtables) {
+            /* set quantization tables header */
+            bytestream_put_byte(&p, 0);
+            bytestream_put_byte(&p, 0);
+            bytestream_put_be16(&p, 64 * nb_qtables);
+
+            for (i = 0; i < nb_qtables; i++)
+                bytestream_put_buffer(&p, &qtables[65 * i + 1], 64);
+        }
+
+        /* copy payload data */
+        memcpy(p, buf, len);
+
+        /* marker bit is last packet in frame */
+        ff_rtp_send_data(s1, s->buf, len + hdr_size, size == len);
+
+        buf  += len;
+        size -= len;
+        off  += len;
+        p     = s->buf;
+    }
+}

libavformat/sdp.c

@@ -547,6 +547,11 @@ static char *sdp_write_media_attributes(char *buff, int size, AVCodecContext *c,
             av_strlcatf(buff, size, "a=rtpmap:%d VP8/90000\r\n",
                                      payload_type);
             break;
+        case AV_CODEC_ID_MJPEG:
+            if (payload_type >= RTP_PT_PRIVATE)
+                av_strlcatf(buff, size, "a=rtpmap:%d JPEG/90000\r\n",
+                                         payload_type);
+            break;
         case AV_CODEC_ID_ADPCM_G722:
             if (payload_type >= RTP_PT_PRIVATE)
                 av_strlcatf(buff, size, "a=rtpmap:%d G722/%d/%d\r\n",

libavformat/version.h

@@ -30,8 +30,8 @@
 #include "libavutil/avutil.h"
 
 #define LIBAVFORMAT_VERSION_MAJOR 54
-#define LIBAVFORMAT_VERSION_MINOR 16
-#define LIBAVFORMAT_VERSION_MICRO  1
+#define LIBAVFORMAT_VERSION_MINOR 17
+#define LIBAVFORMAT_VERSION_MICRO  0
 
 #define LIBAVFORMAT_VERSION_INT AV_VERSION_INT(LIBAVFORMAT_VERSION_MAJOR, \
                                                LIBAVFORMAT_VERSION_MINOR, \