2 * Multipart JPEG format
3 * Copyright (c) 2015 Luca Barbato
5 * This file is part of FFmpeg.
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.
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.
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
22 #include "libavutil/avstring.h"
23 #include "libavutil/opt.h"
27 #include "avio_internal.h"
31 typedef struct MPJPEGDemuxContext {
36 int strict_mime_boundary;
40 static void trim_right(char *p)
48 while (end > p && av_isspace(*(end-1)))
52 static int get_line(AVIOContext *pb, char *line, int line_size)
54 ff_get_line(pb, line, line_size);
68 static int split_tag_value(char **tag, char **value, char *line)
77 while (*p != '\0' && *p != ':') {
78 if (!av_isspace(*p)) {
84 return foundData ? AVERROR_INVALIDDATA : 0;
92 while (av_isspace(*p))
101 static int parse_multipart_header(AVIOContext *pb,
103 const char* expected_boundary,
106 static int mpjpeg_read_close(AVFormatContext *s)
108 MPJPEGDemuxContext *mpjpeg = s->priv_data;
109 av_freep(&mpjpeg->boundary);
110 av_freep(&mpjpeg->searchstr);
114 static int mpjpeg_read_probe(AVProbeData *p)
120 if (p->buf_size < 2 || p->buf[0] != '-' || p->buf[1] != '-')
123 pb = avio_alloc_context(p->buf, p->buf_size, 0, NULL, NULL, NULL, NULL);
127 ret = (parse_multipart_header(pb, &size, "--", NULL) > 0) ? AVPROBE_SCORE_MAX : 0;
134 static int mpjpeg_read_header(AVFormatContext *s)
137 char boundary[70 + 2 + 1] = {0};
138 int64_t pos = avio_tell(s->pb);
142 ret = get_line(s->pb, boundary, sizeof(boundary));
145 } while (!boundary[0]);
147 if (strncmp(boundary, "--", 2))
148 return AVERROR_INVALIDDATA;
150 st = avformat_new_stream(s, NULL);
152 return AVERROR(ENOMEM);
154 st->codec->codec_type = AVMEDIA_TYPE_VIDEO;
155 st->codec->codec_id = AV_CODEC_ID_MJPEG;
157 avpriv_set_pts_info(st, 60, 1, 25);
159 avio_seek(s->pb, pos, SEEK_SET);
164 static int parse_content_length(const char *value)
166 long int val = strtol(value, NULL, 10);
168 if (val == LONG_MIN || val == LONG_MAX)
169 return AVERROR(errno);
171 return AVERROR(ERANGE);
175 static int parse_multipart_header(AVIOContext *pb,
177 const char* expected_boundary,
181 int found_content_type = 0;
186 // get the CRLF as empty string
187 ret = get_line(pb, line, sizeof(line));
191 /* some implementation do not provide the required
192 * initial CRLF (see rfc1341 7.2.1)
195 ret = get_line(pb, line, sizeof(line));
200 if (!av_strstart(line, expected_boundary, NULL)) {
203 "Expected boundary '%s' not found, instead found a line of %zu bytes\n",
207 return AVERROR_INVALIDDATA;
210 while (!pb->eof_reached) {
213 ret = get_line(pb, line, sizeof(line));
215 if (ret == AVERROR_EOF)
223 ret = split_tag_value(&tag, &value, line);
226 if (value==NULL || tag==NULL)
229 if (!av_strcasecmp(tag, "Content-type")) {
230 if (av_strcasecmp(value, "image/jpeg")) {
231 av_log(log_ctx, AV_LOG_ERROR,
232 "Unexpected %s : %s\n",
234 return AVERROR_INVALIDDATA;
236 found_content_type = 1;
237 } else if (!av_strcasecmp(tag, "Content-Length")) {
238 *size = parse_content_length(value);
240 av_log(log_ctx, AV_LOG_WARNING,
241 "Invalid Content-Length value : %s\n",
246 return found_content_type ? 0 : AVERROR_INVALIDDATA;
250 static char* mpjpeg_get_boundary(AVIOContext* pb)
252 uint8_t *mime_type = NULL;
258 /* get MIME type, and skip to the first parameter */
259 av_opt_get(pb, "mime_type", AV_OPT_SEARCH_CHILDREN, &mime_type);
261 while (start != NULL && *start != '\0') {
262 start = strchr(start, ';');
266 while (av_isspace(*start))
269 if (!av_stristart(start, "boundary=", &start)) {
270 end = strchr(start, ';');
272 len = end - start - 1;
275 res = av_strndup(start, len);
280 av_freep(&mime_type);
285 static int mpjpeg_read_packet(AVFormatContext *s, AVPacket *pkt)
290 MPJPEGDemuxContext *mpjpeg = s->priv_data;
291 if (mpjpeg->boundary == NULL) {
292 uint8_t* boundary = NULL;
293 if (mpjpeg->strict_mime_boundary) {
294 boundary = mpjpeg_get_boundary(s->pb);
296 if (boundary != NULL) {
297 mpjpeg->boundary = boundary;
298 mpjpeg->searchstr = av_asprintf( "\r\n%s\r\n", boundary );
300 mpjpeg->boundary = av_strdup("--");
301 mpjpeg->searchstr = av_strdup("\r\n--");
303 if (!mpjpeg->boundary || !mpjpeg->searchstr) {
304 av_freep(&mpjpeg->boundary);
305 av_freep(&mpjpeg->searchstr);
306 return AVERROR(ENOMEM);
308 mpjpeg->searchstr_len = strlen(mpjpeg->searchstr);
311 ret = parse_multipart_header(s->pb, &size, mpjpeg->boundary, s);
318 /* size has been provided to us in MIME header */
319 ret = av_get_packet(s->pb, pkt, size);
321 /* no size was given -- we read until the next boundary or end-of-file */
322 int remaining = 0, len;
324 const int read_chunk = 2048;
328 pkt->pos = avio_tell(s->pb);
330 /* we may need to return as much as all we've read back to the buffer */
331 ffio_ensure_seekback(s->pb, read_chunk);
333 while ((ret = av_append_packet(s->pb, pkt, read_chunk - remaining)) >= 0) {
334 /* scan the new data */
337 len = ret + remaining;
338 start = pkt->data + pkt->size - len;
340 if (!memcmp(start, mpjpeg->searchstr, mpjpeg->searchstr_len)) {
341 // got the boundary! rewind the stream
342 avio_seek(s->pb, -(len-2), SEEK_CUR);
343 pkt->size -= (len-2);
348 } while (len >= mpjpeg->searchstr_len);
352 /* error or EOF occurred */
353 if (ret == AVERROR_EOF) {
354 ret = pkt->size > 0 ? pkt->size : AVERROR_EOF;
356 av_packet_unref(pkt);
363 #define OFFSET(x) offsetof(MPJPEGDemuxContext, x)
365 #define DEC AV_OPT_FLAG_DECODING_PARAM
366 const AVOption mpjpeg_options[] = {
367 { "strict_mime_boundary", "require MIME boundaries match", OFFSET(strict_mime_boundary), AV_OPT_TYPE_BOOL, {.i64 = 0}, 0, 1, DEC },
372 static const AVClass mpjpeg_demuxer_class = {
373 .class_name = "MPJPEG demuxer",
374 .item_name = av_default_item_name,
375 .option = mpjpeg_options,
376 .version = LIBAVUTIL_VERSION_INT,
379 AVInputFormat ff_mpjpeg_demuxer = {
381 .long_name = NULL_IF_CONFIG_SMALL("MIME multipart JPEG"),
382 .mime_type = "multipart/x-mixed-replace",
383 .extensions = "mjpg",
384 .priv_data_size = sizeof(MPJPEGDemuxContext),
385 .read_probe = mpjpeg_read_probe,
386 .read_header = mpjpeg_read_header,
387 .read_packet = mpjpeg_read_packet,
388 .read_close = mpjpeg_read_close,
389 .priv_class = &mpjpeg_demuxer_class