/* * 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; 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); /* get the pixel format type or fail */ if (s1->streams[0]->codecpar->format == AV_PIX_FMT_YUVJ422P || (s1->streams[0]->codecpar->color_range == AVCOL_RANGE_JPEG && s1->streams[0]->codecpar->format == AV_PIX_FMT_YUV422P)) { type = 0; } else if (s1->streams[0]->codecpar->format == AV_PIX_FMT_YUVJ420P || (s1->streams[0]->codecpar->color_range == AVCOL_RANGE_JPEG && s1->streams[0]->codecpar->format == AV_PIX_FMT_YUV420P)) { type = 1; } else { av_log(s1, AV_LOG_ERROR, "Unsupported pixel format\n"); return; } /* 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; } } 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; } } 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; } }