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Diffstat (limited to 'ffmpeg/libavformat/rtpdec_h264.c')
-rw-r--r--ffmpeg/libavformat/rtpdec_h264.c399
1 files changed, 399 insertions, 0 deletions
diff --git a/ffmpeg/libavformat/rtpdec_h264.c b/ffmpeg/libavformat/rtpdec_h264.c
new file mode 100644
index 0000000..d1133b7
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+++ b/ffmpeg/libavformat/rtpdec_h264.c
@@ -0,0 +1,399 @@
+/*
+ * RTP H264 Protocol (RFC3984)
+ * Copyright (c) 2006 Ryan Martell
+ *
+ * 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
+ */
+
+/**
+ * @file
+ * @brief H.264 / RTP Code (RFC3984)
+ * @author Ryan Martell <rdm4@martellventures.com>
+ *
+ * @note Notes:
+ * Notes:
+ * This currently supports packetization mode:
+ * Single Nal Unit Mode (0), or
+ * Non-Interleaved Mode (1). It currently does not support
+ * Interleaved Mode (2). (This requires implementing STAP-B, MTAP16, MTAP24,
+ * FU-B packet types)
+ */
+
+#include "libavutil/base64.h"
+#include "libavutil/avstring.h"
+#include "libavcodec/get_bits.h"
+#include "avformat.h"
+
+#include "network.h"
+#include <assert.h>
+
+#include "rtpdec.h"
+#include "rtpdec_formats.h"
+
+struct PayloadContext {
+ // sdp setup parameters
+ uint8_t profile_idc;
+ uint8_t profile_iop;
+ uint8_t level_idc;
+ int packetization_mode;
+#ifdef DEBUG
+ int packet_types_received[32];
+#endif
+};
+
+#ifdef DEBUG
+#define COUNT_NAL_TYPE(data, nal) data->packet_types_received[(nal) & 0x1f]++
+#else
+#define COUNT_NAL_TYPE(data, nal) do { } while (0)
+#endif
+
+static const uint8_t start_sequence[] = { 0, 0, 0, 1 };
+
+static int sdp_parse_fmtp_config_h264(AVStream *stream,
+ PayloadContext *h264_data,
+ char *attr, char *value)
+{
+ AVCodecContext *codec = stream->codec;
+ assert(codec->codec_id == AV_CODEC_ID_H264);
+ assert(h264_data != NULL);
+
+ if (!strcmp(attr, "packetization-mode")) {
+ av_log(codec, AV_LOG_DEBUG, "RTP Packetization Mode: %d\n", atoi(value));
+ h264_data->packetization_mode = atoi(value);
+ /*
+ * Packetization Mode:
+ * 0 or not present: Single NAL mode (Only nals from 1-23 are allowed)
+ * 1: Non-interleaved Mode: 1-23, 24 (STAP-A), 28 (FU-A) are allowed.
+ * 2: Interleaved Mode: 25 (STAP-B), 26 (MTAP16), 27 (MTAP24), 28 (FU-A),
+ * and 29 (FU-B) are allowed.
+ */
+ if (h264_data->packetization_mode > 1)
+ av_log(codec, AV_LOG_ERROR,
+ "Interleaved RTP mode is not supported yet.\n");
+ } else if (!strcmp(attr, "profile-level-id")) {
+ if (strlen(value) == 6) {
+ char buffer[3];
+ // 6 characters=3 bytes, in hex.
+ uint8_t profile_idc;
+ uint8_t profile_iop;
+ uint8_t level_idc;
+
+ buffer[0] = value[0];
+ buffer[1] = value[1];
+ buffer[2] = '\0';
+ profile_idc = strtol(buffer, NULL, 16);
+ buffer[0] = value[2];
+ buffer[1] = value[3];
+ profile_iop = strtol(buffer, NULL, 16);
+ buffer[0] = value[4];
+ buffer[1] = value[5];
+ level_idc = strtol(buffer, NULL, 16);
+
+ av_log(codec, AV_LOG_DEBUG,
+ "RTP Profile IDC: %x Profile IOP: %x Level: %x\n",
+ profile_idc, profile_iop, level_idc);
+ h264_data->profile_idc = profile_idc;
+ h264_data->profile_iop = profile_iop;
+ h264_data->level_idc = level_idc;
+ }
+ } else if (!strcmp(attr, "sprop-parameter-sets")) {
+ codec->extradata_size = 0;
+ av_freep(&codec->extradata);
+
+ while (*value) {
+ char base64packet[1024];
+ uint8_t decoded_packet[1024];
+ int packet_size;
+ char *dst = base64packet;
+
+ while (*value && *value != ','
+ && (dst - base64packet) < sizeof(base64packet) - 1) {
+ *dst++ = *value++;
+ }
+ *dst++ = '\0';
+
+ if (*value == ',')
+ value++;
+
+ packet_size = av_base64_decode(decoded_packet, base64packet,
+ sizeof(decoded_packet));
+ if (packet_size > 0) {
+ uint8_t *dest = av_malloc(packet_size + sizeof(start_sequence) +
+ codec->extradata_size +
+ FF_INPUT_BUFFER_PADDING_SIZE);
+ if (!dest) {
+ av_log(codec, AV_LOG_ERROR,
+ "Unable to allocate memory for extradata!\n");
+ return AVERROR(ENOMEM);
+ }
+ if (codec->extradata_size) {
+ memcpy(dest, codec->extradata, codec->extradata_size);
+ av_free(codec->extradata);
+ }
+
+ memcpy(dest + codec->extradata_size, start_sequence,
+ sizeof(start_sequence));
+ memcpy(dest + codec->extradata_size + sizeof(start_sequence),
+ decoded_packet, packet_size);
+ memset(dest + codec->extradata_size + sizeof(start_sequence) +
+ packet_size, 0, FF_INPUT_BUFFER_PADDING_SIZE);
+
+ codec->extradata = dest;
+ codec->extradata_size += sizeof(start_sequence) + packet_size;
+ }
+ }
+ av_log(codec, AV_LOG_DEBUG, "Extradata set to %p (size: %d)!\n",
+ codec->extradata, codec->extradata_size);
+ }
+ return 0;
+}
+
+// return 0 on packet, no more left, 1 on packet, 1 on partial packet
+static int h264_handle_packet(AVFormatContext *ctx, PayloadContext *data,
+ AVStream *st, AVPacket *pkt, uint32_t *timestamp,
+ const uint8_t *buf, int len, uint16_t seq,
+ int flags)
+{
+ uint8_t nal;
+ uint8_t type;
+ int result = 0;
+
+ if (!len) {
+ av_log(ctx, AV_LOG_ERROR, "Empty H264 RTP packet\n");
+ return AVERROR_INVALIDDATA;
+ }
+ nal = buf[0];
+ type = nal & 0x1f;
+
+ assert(data);
+ assert(buf);
+
+ /* Simplify the case (these are all the nal types used internally by
+ * the h264 codec). */
+ if (type >= 1 && type <= 23)
+ type = 1;
+ switch (type) {
+ case 0: // undefined, but pass them through
+ case 1:
+ av_new_packet(pkt, len + sizeof(start_sequence));
+ memcpy(pkt->data, start_sequence, sizeof(start_sequence));
+ memcpy(pkt->data + sizeof(start_sequence), buf, len);
+ COUNT_NAL_TYPE(data, nal);
+ break;
+
+ case 24: // STAP-A (one packet, multiple nals)
+ // consume the STAP-A NAL
+ buf++;
+ len--;
+ // first we are going to figure out the total size
+ {
+ int pass = 0;
+ int total_length = 0;
+ uint8_t *dst = NULL;
+
+ for (pass = 0; pass < 2; pass++) {
+ const uint8_t *src = buf;
+ int src_len = len;
+
+ while (src_len > 2) {
+ uint16_t nal_size = AV_RB16(src);
+
+ // consume the length of the aggregate
+ src += 2;
+ src_len -= 2;
+
+ if (nal_size <= src_len) {
+ if (pass == 0) {
+ // counting
+ total_length += sizeof(start_sequence) + nal_size;
+ } else {
+ // copying
+ assert(dst);
+ memcpy(dst, start_sequence, sizeof(start_sequence));
+ dst += sizeof(start_sequence);
+ memcpy(dst, src, nal_size);
+ COUNT_NAL_TYPE(data, *src);
+ dst += nal_size;
+ }
+ } else {
+ av_log(ctx, AV_LOG_ERROR,
+ "nal size exceeds length: %d %d\n", nal_size, src_len);
+ }
+
+ // eat what we handled
+ src += nal_size;
+ src_len -= nal_size;
+
+ if (src_len < 0)
+ av_log(ctx, AV_LOG_ERROR,
+ "Consumed more bytes than we got! (%d)\n", src_len);
+ }
+
+ if (pass == 0) {
+ /* now we know the total size of the packet (with the
+ * start sequences added) */
+ av_new_packet(pkt, total_length);
+ dst = pkt->data;
+ } else {
+ assert(dst - pkt->data == total_length);
+ }
+ }
+ }
+ break;
+
+ case 25: // STAP-B
+ case 26: // MTAP-16
+ case 27: // MTAP-24
+ case 29: // FU-B
+ av_log(ctx, AV_LOG_ERROR,
+ "Unhandled type (%d) (See RFC for implementation details\n",
+ type);
+ result = AVERROR(ENOSYS);
+ break;
+
+ case 28: // FU-A (fragmented nal)
+ buf++;
+ len--; // skip the fu_indicator
+ if (len > 1) {
+ // these are the same as above, we just redo them here for clarity
+ uint8_t fu_indicator = nal;
+ uint8_t fu_header = *buf;
+ uint8_t start_bit = fu_header >> 7;
+ uint8_t av_unused end_bit = (fu_header & 0x40) >> 6;
+ uint8_t nal_type = fu_header & 0x1f;
+ uint8_t reconstructed_nal;
+
+ // Reconstruct this packet's true nal; only the data follows.
+ /* The original nal forbidden bit and NRI are stored in this
+ * packet's nal. */
+ reconstructed_nal = fu_indicator & 0xe0;
+ reconstructed_nal |= nal_type;
+
+ // skip the fu_header
+ buf++;
+ len--;
+
+ if (start_bit)
+ COUNT_NAL_TYPE(data, nal_type);
+ if (start_bit) {
+ /* copy in the start sequence, and the reconstructed nal */
+ av_new_packet(pkt, sizeof(start_sequence) + sizeof(nal) + len);
+ memcpy(pkt->data, start_sequence, sizeof(start_sequence));
+ pkt->data[sizeof(start_sequence)] = reconstructed_nal;
+ memcpy(pkt->data + sizeof(start_sequence) + sizeof(nal), buf, len);
+ } else {
+ av_new_packet(pkt, len);
+ memcpy(pkt->data, buf, len);
+ }
+ } else {
+ av_log(ctx, AV_LOG_ERROR, "Too short data for FU-A H264 RTP packet\n");
+ result = AVERROR_INVALIDDATA;
+ }
+ break;
+
+ case 30: // undefined
+ case 31: // undefined
+ default:
+ av_log(ctx, AV_LOG_ERROR, "Undefined type (%d)\n", type);
+ result = AVERROR_INVALIDDATA;
+ break;
+ }
+
+ pkt->stream_index = st->index;
+
+ return result;
+}
+
+static PayloadContext *h264_new_context(void)
+{
+ return av_mallocz(sizeof(PayloadContext) + FF_INPUT_BUFFER_PADDING_SIZE);
+}
+
+static void h264_free_context(PayloadContext *data)
+{
+#ifdef DEBUG
+ int ii;
+
+ for (ii = 0; ii < 32; ii++) {
+ if (data->packet_types_received[ii])
+ av_log(NULL, AV_LOG_DEBUG, "Received %d packets of type %d\n",
+ data->packet_types_received[ii], ii);
+ }
+#endif
+
+ av_free(data);
+}
+
+static int h264_init(AVFormatContext *s, int st_index, PayloadContext *data)
+{
+ if (st_index < 0)
+ return 0;
+ s->streams[st_index]->need_parsing = AVSTREAM_PARSE_FULL;
+ return 0;
+}
+
+static int parse_h264_sdp_line(AVFormatContext *s, int st_index,
+ PayloadContext *h264_data, const char *line)
+{
+ AVStream *stream;
+ AVCodecContext *codec;
+ const char *p = line;
+
+ if (st_index < 0)
+ return 0;
+
+ stream = s->streams[st_index];
+ codec = stream->codec;
+
+ if (av_strstart(p, "framesize:", &p)) {
+ char buf1[50];
+ char *dst = buf1;
+
+ // remove the protocol identifier
+ while (*p && *p == ' ')
+ p++; // strip spaces.
+ while (*p && *p != ' ')
+ p++; // eat protocol identifier
+ while (*p && *p == ' ')
+ p++; // strip trailing spaces.
+ while (*p && *p != '-' && (dst - buf1) < sizeof(buf1) - 1)
+ *dst++ = *p++;
+ *dst = '\0';
+
+ // a='framesize:96 320-240'
+ // set our parameters
+ codec->width = atoi(buf1);
+ codec->height = atoi(p + 1); // skip the -
+ } else if (av_strstart(p, "fmtp:", &p)) {
+ return ff_parse_fmtp(stream, h264_data, p, sdp_parse_fmtp_config_h264);
+ } else if (av_strstart(p, "cliprect:", &p)) {
+ // could use this if we wanted.
+ }
+
+ return 0;
+}
+
+RTPDynamicProtocolHandler ff_h264_dynamic_handler = {
+ .enc_name = "H264",
+ .codec_type = AVMEDIA_TYPE_VIDEO,
+ .codec_id = AV_CODEC_ID_H264,
+ .init = h264_init,
+ .parse_sdp_a_line = parse_h264_sdp_line,
+ .alloc = h264_new_context,
+ .free = h264_free_context,
+ .parse_packet = h264_handle_packet
+};
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