| 1 | /* |
| 2 | * RTP JPEG-compressed video Packetizer, RFC 2435 |
| 3 | * Copyright (c) 2012 Samuel Pitoiset |
| 4 | * |
| 5 | * This file is part of FFmpeg. |
| 6 | * |
| 7 | * FFmpeg is free software; you can redistribute it and/or |
| 8 | * modify it under the terms of the GNU Lesser General Public |
| 9 | * License as published by the Free Software Foundation; either |
| 10 | * version 2.1 of the License, or (at your option) any later version. |
| 11 | * |
| 12 | * FFmpeg is distributed in the hope that it will be useful, |
| 13 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 14 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 15 | * Lesser General Public License for more details. |
| 16 | * |
| 17 | * You should have received a copy of the GNU Lesser General Public |
| 18 | * License along with FFmpeg; if not, write to the Free Software |
| 19 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
| 20 | */ |
| 21 | |
| 22 | #include "libavcodec/bytestream.h" |
| 23 | #include "libavcodec/mjpeg.h" |
| 24 | #include "libavutil/intreadwrite.h" |
| 25 | #include "rtpenc.h" |
| 26 | |
| 27 | void ff_rtp_send_jpeg(AVFormatContext *s1, const uint8_t *buf, int size) |
| 28 | { |
| 29 | RTPMuxContext *s = s1->priv_data; |
| 30 | const uint8_t *qtables = NULL; |
| 31 | int nb_qtables = 0; |
| 32 | uint8_t type; |
| 33 | uint8_t w, h; |
| 34 | uint8_t *p; |
| 35 | int off = 0; /* fragment offset of the current JPEG frame */ |
| 36 | int len; |
| 37 | int i; |
| 38 | |
| 39 | s->buf_ptr = s->buf; |
| 40 | s->timestamp = s->cur_timestamp; |
| 41 | |
| 42 | /* convert video pixel dimensions from pixels to blocks */ |
| 43 | w = s1->streams[0]->codec->width >> 3; |
| 44 | h = s1->streams[0]->codec->height >> 3; |
| 45 | |
| 46 | /* get the pixel format type or fail */ |
| 47 | if (s1->streams[0]->codec->pix_fmt == AV_PIX_FMT_YUVJ422P || |
| 48 | (s1->streams[0]->codec->color_range == AVCOL_RANGE_JPEG && |
| 49 | s1->streams[0]->codec->pix_fmt == AV_PIX_FMT_YUV422P)) { |
| 50 | type = 0; |
| 51 | } else if (s1->streams[0]->codec->pix_fmt == AV_PIX_FMT_YUVJ420P || |
| 52 | (s1->streams[0]->codec->color_range == AVCOL_RANGE_JPEG && |
| 53 | s1->streams[0]->codec->pix_fmt == AV_PIX_FMT_YUV420P)) { |
| 54 | type = 1; |
| 55 | } else { |
| 56 | av_log(s1, AV_LOG_ERROR, "Unsupported pixel format\n"); |
| 57 | return; |
| 58 | } |
| 59 | |
| 60 | /* preparse the header for getting some infos */ |
| 61 | for (i = 0; i < size; i++) { |
| 62 | if (buf[i] != 0xff) |
| 63 | continue; |
| 64 | |
| 65 | if (buf[i + 1] == DQT) { |
| 66 | if (buf[i + 4]) |
| 67 | av_log(s1, AV_LOG_WARNING, |
| 68 | "Only 8-bit precision is supported.\n"); |
| 69 | |
| 70 | /* a quantization table is 64 bytes long */ |
| 71 | nb_qtables = AV_RB16(&buf[i + 2]) / 65; |
| 72 | if (i + 4 + nb_qtables * 65 > size) { |
| 73 | av_log(s1, AV_LOG_ERROR, "Too short JPEG header. Aborted!\n"); |
| 74 | return; |
| 75 | } |
| 76 | |
| 77 | qtables = &buf[i + 4]; |
| 78 | } else if (buf[i + 1] == SOF0) { |
| 79 | if (buf[i + 14] != 17 || buf[i + 17] != 17) { |
| 80 | av_log(s1, AV_LOG_ERROR, |
| 81 | "Only 1x1 chroma blocks are supported. Aborted!\n"); |
| 82 | return; |
| 83 | } |
| 84 | } else if (buf[i + 1] == SOS) { |
| 85 | /* SOS is last marker in the header */ |
| 86 | i += AV_RB16(&buf[i + 2]) + 2; |
| 87 | break; |
| 88 | } |
| 89 | } |
| 90 | |
| 91 | /* skip JPEG header */ |
| 92 | buf += i; |
| 93 | size -= i; |
| 94 | |
| 95 | for (i = size - 2; i >= 0; i--) { |
| 96 | if (buf[i] == 0xff && buf[i + 1] == EOI) { |
| 97 | /* Remove the EOI marker */ |
| 98 | size = i; |
| 99 | break; |
| 100 | } |
| 101 | } |
| 102 | |
| 103 | p = s->buf_ptr; |
| 104 | while (size > 0) { |
| 105 | int hdr_size = 8; |
| 106 | |
| 107 | if (off == 0 && nb_qtables) |
| 108 | hdr_size += 4 + 64 * nb_qtables; |
| 109 | |
| 110 | /* payload max in one packet */ |
| 111 | len = FFMIN(size, s->max_payload_size - hdr_size); |
| 112 | |
| 113 | /* set main header */ |
| 114 | bytestream_put_byte(&p, 0); |
| 115 | bytestream_put_be24(&p, off); |
| 116 | bytestream_put_byte(&p, type); |
| 117 | bytestream_put_byte(&p, 255); |
| 118 | bytestream_put_byte(&p, w); |
| 119 | bytestream_put_byte(&p, h); |
| 120 | |
| 121 | if (off == 0 && nb_qtables) { |
| 122 | /* set quantization tables header */ |
| 123 | bytestream_put_byte(&p, 0); |
| 124 | bytestream_put_byte(&p, 0); |
| 125 | bytestream_put_be16(&p, 64 * nb_qtables); |
| 126 | |
| 127 | for (i = 0; i < nb_qtables; i++) |
| 128 | bytestream_put_buffer(&p, &qtables[65 * i + 1], 64); |
| 129 | } |
| 130 | |
| 131 | /* copy payload data */ |
| 132 | memcpy(p, buf, len); |
| 133 | |
| 134 | /* marker bit is last packet in frame */ |
| 135 | ff_rtp_send_data(s1, s->buf, len + hdr_size, size == len); |
| 136 | |
| 137 | buf += len; |
| 138 | size -= len; |
| 139 | off += len; |
| 140 | p = s->buf; |
| 141 | } |
| 142 | } |