| /* | |
| * RTP JPEG-compressed video Packetizer, RFC 2435 | |
| * Copyright (c) 2012 Samuel Pitoiset | |
| * | |
| * This file is part of FFmpeg. | |
| * | |
| * FFmpeg 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. | |
| * | |
| * FFmpeg 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 FFmpeg; 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 "libavcodec/jpegtables.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[4] = { NULL }; | |
| int nb_qtables = 0; | |
| uint8_t type = 2; /* initialized non-0/1 value for RTP/JPEG type check*/ | |
| uint8_t w, h; | |
| uint8_t *p; | |
| int off = 0; /* fragment offset of the current JPEG frame */ | |
| int len; | |
| int i; | |
| int default_huffman_tables = 0; | |
| s->buf_ptr = s->buf; | |
| s->timestamp = s->cur_timestamp; | |
| /* convert video pixel dimensions from pixels to blocks */ | |
| w = AV_CEIL_RSHIFT(s1->streams[0]->codecpar->width, 3); | |
| h = AV_CEIL_RSHIFT(s1->streams[0]->codecpar->height, 3); | |
| /* preparse the header for getting some info */ | |
| for (i = 0; i < size; i++) { | |
| if (buf[i] != 0xff) | |
| continue; | |
| if (buf[i + 1] == DQT) { | |
| int tables, j; | |
| if (buf[i + 4] & 0xF0) | |
| av_log(s1, AV_LOG_WARNING, | |
| "Only 8-bit precision is supported.\n"); | |
| /* a quantization table is 64 bytes long */ | |
| tables = AV_RB16(&buf[i + 2]) / 65; | |
| if (i + 5 + tables * 65 > size) { | |
| av_log(s1, AV_LOG_ERROR, "Too short JPEG header. Aborted!\n"); | |
| return; | |
| } | |
| if (nb_qtables + tables > 4) { | |
| av_log(s1, AV_LOG_ERROR, "Invalid number of quantisation tables\n"); | |
| return; | |
| } | |
| for (j = 0; j < tables; j++) | |
| qtables[nb_qtables + j] = buf + i + 5 + j * 65; | |
| nb_qtables += tables; | |
| } 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; | |
| } | |
| /* | |
| * Find out the sampling factor in SOF0. | |
| * In SOF0, hsample/vsample is inserted in form of (2<<4) | (type ? 2 : 1). | |
| * First 4-bit is hsample while Last 4-bit is vsample. | |
| */ | |
| /* Luma channel sampling factor in 4:2:2 chroma subsampling are 2x1 */ | |
| if (buf[i + 11] == 33) { | |
| type = 0; | |
| /* Luma channel sampling factor in 4:2:0 chroma subsampling are 2x2 */ | |
| } else if (buf[i + 11] == 34) { | |
| type = 1; | |
| } else { | |
| av_log(s1, AV_LOG_ERROR, "Unsupported pixel format\n"); | |
| return; | |
| } | |
| } else if (buf[i + 1] == DHT) { | |
| int dht_size = AV_RB16(&buf[i + 2]); | |
| default_huffman_tables |= 1 << 4; | |
| i += 3; | |
| dht_size -= 2; | |
| if (i + dht_size >= size) | |
| continue; | |
| while (dht_size > 0) | |
| switch (buf[i + 1]) { | |
| case 0x00: | |
| if ( dht_size >= 29 | |
| && !memcmp(buf + i + 2, ff_mjpeg_bits_dc_luminance + 1, 16) | |
| && !memcmp(buf + i + 18, ff_mjpeg_val_dc, 12)) { | |
| default_huffman_tables |= 1; | |
| i += 29; | |
| dht_size -= 29; | |
| } else { | |
| i += dht_size; | |
| dht_size = 0; | |
| } | |
| break; | |
| case 0x01: | |
| if ( dht_size >= 29 | |
| && !memcmp(buf + i + 2, ff_mjpeg_bits_dc_chrominance + 1, 16) | |
| && !memcmp(buf + i + 18, ff_mjpeg_val_dc, 12)) { | |
| default_huffman_tables |= 1 << 1; | |
| i += 29; | |
| dht_size -= 29; | |
| } else { | |
| i += dht_size; | |
| dht_size = 0; | |
| } | |
| break; | |
| case 0x10: | |
| if ( dht_size >= 179 | |
| && !memcmp(buf + i + 2, ff_mjpeg_bits_ac_luminance + 1, 16) | |
| && !memcmp(buf + i + 18, ff_mjpeg_val_ac_luminance, 162)) { | |
| default_huffman_tables |= 1 << 2; | |
| i += 179; | |
| dht_size -= 179; | |
| } else { | |
| i += dht_size; | |
| dht_size = 0; | |
| } | |
| break; | |
| case 0x11: | |
| if ( dht_size >= 179 | |
| && !memcmp(buf + i + 2, ff_mjpeg_bits_ac_chrominance + 1, 16) | |
| && !memcmp(buf + i + 18, ff_mjpeg_val_ac_chrominance, 162)) { | |
| default_huffman_tables |= 1 << 3; | |
| i += 179; | |
| dht_size -= 179; | |
| } else { | |
| i += dht_size; | |
| dht_size = 0; | |
| } | |
| break; | |
| default: | |
| i += dht_size; | |
| dht_size = 0; | |
| continue; | |
| } | |
| } else if (buf[i + 1] == SOS) { | |
| /* SOS is last marker in the header */ | |
| i += AV_RB16(&buf[i + 2]) + 2; | |
| if (i > size) { | |
| av_log(s1, AV_LOG_ERROR, | |
| "Insufficient data. Aborted!\n"); | |
| return; | |
| } | |
| break; | |
| } | |
| } | |
| /* Check validity of RTP/JPEG type */ | |
| if (type != 0 && type != 1) { | |
| av_log(s1, AV_LOG_ERROR, | |
| "Invalid RTP/JPEG type\n"); | |
| return; | |
| } | |
| if (default_huffman_tables && default_huffman_tables != 31) { | |
| av_log(s1, AV_LOG_ERROR, | |
| "RFC 2435 requires standard Huffman tables for jpeg\n"); | |
| return; | |
| } | |
| if (nb_qtables && nb_qtables != 2) | |
| av_log(s1, AV_LOG_WARNING, | |
| "RFC 2435 suggests two quantization tables, %d provided\n", | |
| nb_qtables); | |
| /* 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[i], 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; | |
| } | |
| } |