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libavformat/applehttp.c

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00001 /*
00002  * Apple HTTP Live Streaming demuxer
00003  * Copyright (c) 2010 Martin Storsjo
00004  *
00005  * This file is part of FFmpeg.
00006  *
00007  * FFmpeg is free software; you can redistribute it and/or
00008  * modify it under the terms of the GNU Lesser General Public
00009  * License as published by the Free Software Foundation; either
00010  * version 2.1 of the License, or (at your option) any later version.
00011  *
00012  * FFmpeg is distributed in the hope that it will be useful,
00013  * but WITHOUT ANY WARRANTY; without even the implied warranty of
00014  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
00015  * Lesser General Public License for more details.
00016  *
00017  * You should have received a copy of the GNU Lesser General Public
00018  * License along with FFmpeg; if not, write to the Free Software
00019  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
00020  */
00021 
00028 #include "libavutil/avstring.h"
00029 #include "libavutil/intreadwrite.h"
00030 #include "libavutil/opt.h"
00031 #include "libavutil/dict.h"
00032 #include "avformat.h"
00033 #include "internal.h"
00034 #include <unistd.h>
00035 #include "avio_internal.h"
00036 #include "url.h"
00037 
00038 #define INITIAL_BUFFER_SIZE 32768
00039 
00040 /*
00041  * An apple http stream consists of a playlist with media segment files,
00042  * played sequentially. There may be several playlists with the same
00043  * video content, in different bandwidth variants, that are played in
00044  * parallel (preferrably only one bandwidth variant at a time). In this case,
00045  * the user supplied the url to a main playlist that only lists the variant
00046  * playlists.
00047  *
00048  * If the main playlist doesn't point at any variants, we still create
00049  * one anonymous toplevel variant for this, to maintain the structure.
00050  */
00051 
00052 enum KeyType {
00053     KEY_NONE,
00054     KEY_AES_128,
00055 };
00056 
00057 struct segment {
00058     int duration;
00059     char url[MAX_URL_SIZE];
00060     char key[MAX_URL_SIZE];
00061     enum KeyType key_type;
00062     uint8_t iv[16];
00063 };
00064 
00065 /*
00066  * Each variant has its own demuxer. If it currently is active,
00067  * it has an open AVIOContext too, and potentially an AVPacket
00068  * containing the next packet from this stream.
00069  */
00070 struct variant {
00071     int bandwidth;
00072     char url[MAX_URL_SIZE];
00073     AVIOContext pb;
00074     uint8_t* read_buffer;
00075     URLContext *input;
00076     AVFormatContext *parent;
00077     int index;
00078     AVFormatContext *ctx;
00079     AVPacket pkt;
00080     int stream_offset;
00081 
00082     int finished;
00083     int target_duration;
00084     int start_seq_no;
00085     int n_segments;
00086     struct segment **segments;
00087     int needed, cur_needed;
00088     int cur_seq_no;
00089     int64_t last_load_time;
00090 
00091     char key_url[MAX_URL_SIZE];
00092     uint8_t key[16];
00093 };
00094 
00095 typedef struct AppleHTTPContext {
00096     int n_variants;
00097     struct variant **variants;
00098     int cur_seq_no;
00099     int end_of_segment;
00100     int first_packet;
00101 } AppleHTTPContext;
00102 
00103 static int read_chomp_line(AVIOContext *s, char *buf, int maxlen)
00104 {
00105     int len = ff_get_line(s, buf, maxlen);
00106     while (len > 0 && isspace(buf[len - 1]))
00107         buf[--len] = '\0';
00108     return len;
00109 }
00110 
00111 static void free_segment_list(struct variant *var)
00112 {
00113     int i;
00114     for (i = 0; i < var->n_segments; i++)
00115         av_free(var->segments[i]);
00116     av_freep(&var->segments);
00117     var->n_segments = 0;
00118 }
00119 
00120 static void free_variant_list(AppleHTTPContext *c)
00121 {
00122     int i;
00123     for (i = 0; i < c->n_variants; i++) {
00124         struct variant *var = c->variants[i];
00125         free_segment_list(var);
00126         av_free_packet(&var->pkt);
00127         av_free(var->pb.buffer);
00128         if (var->input)
00129             ffurl_close(var->input);
00130         if (var->ctx) {
00131             var->ctx->pb = NULL;
00132             av_close_input_file(var->ctx);
00133         }
00134         av_free(var);
00135     }
00136     av_freep(&c->variants);
00137     c->n_variants = 0;
00138 }
00139 
00140 /*
00141  * Used to reset a statically allocated AVPacket to a clean slate,
00142  * containing no data.
00143  */
00144 static void reset_packet(AVPacket *pkt)
00145 {
00146     av_init_packet(pkt);
00147     pkt->data = NULL;
00148 }
00149 
00150 static struct variant *new_variant(AppleHTTPContext *c, int bandwidth,
00151                                    const char *url, const char *base)
00152 {
00153     struct variant *var = av_mallocz(sizeof(struct variant));
00154     if (!var)
00155         return NULL;
00156     reset_packet(&var->pkt);
00157     var->bandwidth = bandwidth;
00158     ff_make_absolute_url(var->url, sizeof(var->url), base, url);
00159     dynarray_add(&c->variants, &c->n_variants, var);
00160     return var;
00161 }
00162 
00163 struct variant_info {
00164     char bandwidth[20];
00165 };
00166 
00167 static void handle_variant_args(struct variant_info *info, const char *key,
00168                                 int key_len, char **dest, int *dest_len)
00169 {
00170     if (!strncmp(key, "BANDWIDTH=", key_len)) {
00171         *dest     =        info->bandwidth;
00172         *dest_len = sizeof(info->bandwidth);
00173     }
00174 }
00175 
00176 struct key_info {
00177      char uri[MAX_URL_SIZE];
00178      char method[10];
00179      char iv[35];
00180 };
00181 
00182 static void handle_key_args(struct key_info *info, const char *key,
00183                             int key_len, char **dest, int *dest_len)
00184 {
00185     if (!strncmp(key, "METHOD=", key_len)) {
00186         *dest     =        info->method;
00187         *dest_len = sizeof(info->method);
00188     } else if (!strncmp(key, "URI=", key_len)) {
00189         *dest     =        info->uri;
00190         *dest_len = sizeof(info->uri);
00191     } else if (!strncmp(key, "IV=", key_len)) {
00192         *dest     =        info->iv;
00193         *dest_len = sizeof(info->iv);
00194     }
00195 }
00196 
00197 static int parse_playlist(AppleHTTPContext *c, const char *url,
00198                           struct variant *var, AVIOContext *in)
00199 {
00200     int ret = 0, duration = 0, is_segment = 0, is_variant = 0, bandwidth = 0;
00201     enum KeyType key_type = KEY_NONE;
00202     uint8_t iv[16] = "";
00203     int has_iv = 0;
00204     char key[MAX_URL_SIZE];
00205     char line[1024];
00206     const char *ptr;
00207     int close_in = 0;
00208 
00209     if (!in) {
00210         close_in = 1;
00211         if ((ret = avio_open(&in, url, AVIO_RDONLY)) < 0)
00212             return ret;
00213     }
00214 
00215     read_chomp_line(in, line, sizeof(line));
00216     if (strcmp(line, "#EXTM3U")) {
00217         ret = AVERROR_INVALIDDATA;
00218         goto fail;
00219     }
00220 
00221     if (var) {
00222         free_segment_list(var);
00223         var->finished = 0;
00224     }
00225     while (!url_feof(in)) {
00226         read_chomp_line(in, line, sizeof(line));
00227         if (av_strstart(line, "#EXT-X-STREAM-INF:", &ptr)) {
00228             struct variant_info info = {{0}};
00229             is_variant = 1;
00230             ff_parse_key_value(ptr, (ff_parse_key_val_cb) handle_variant_args,
00231                                &info);
00232             bandwidth = atoi(info.bandwidth);
00233         } else if (av_strstart(line, "#EXT-X-KEY:", &ptr)) {
00234             struct key_info info = {{0}};
00235             ff_parse_key_value(ptr, (ff_parse_key_val_cb) handle_key_args,
00236                                &info);
00237             key_type = KEY_NONE;
00238             has_iv = 0;
00239             if (!strcmp(info.method, "AES-128"))
00240                 key_type = KEY_AES_128;
00241             if (!strncmp(info.iv, "0x", 2) || !strncmp(info.iv, "0X", 2)) {
00242                 ff_hex_to_data(iv, info.iv + 2);
00243                 has_iv = 1;
00244             }
00245             av_strlcpy(key, info.uri, sizeof(key));
00246         } else if (av_strstart(line, "#EXT-X-TARGETDURATION:", &ptr)) {
00247             if (!var) {
00248                 var = new_variant(c, 0, url, NULL);
00249                 if (!var) {
00250                     ret = AVERROR(ENOMEM);
00251                     goto fail;
00252                 }
00253             }
00254             var->target_duration = atoi(ptr);
00255         } else if (av_strstart(line, "#EXT-X-MEDIA-SEQUENCE:", &ptr)) {
00256             if (!var) {
00257                 var = new_variant(c, 0, url, NULL);
00258                 if (!var) {
00259                     ret = AVERROR(ENOMEM);
00260                     goto fail;
00261                 }
00262             }
00263             var->start_seq_no = atoi(ptr);
00264         } else if (av_strstart(line, "#EXT-X-ENDLIST", &ptr)) {
00265             if (var)
00266                 var->finished = 1;
00267         } else if (av_strstart(line, "#EXTINF:", &ptr)) {
00268             is_segment = 1;
00269             duration   = atoi(ptr);
00270         } else if (av_strstart(line, "#", NULL)) {
00271             continue;
00272         } else if (line[0]) {
00273             if (is_variant) {
00274                 if (!new_variant(c, bandwidth, line, url)) {
00275                     ret = AVERROR(ENOMEM);
00276                     goto fail;
00277                 }
00278                 is_variant = 0;
00279                 bandwidth  = 0;
00280             }
00281             if (is_segment) {
00282                 struct segment *seg;
00283                 if (!var) {
00284                     var = new_variant(c, 0, url, NULL);
00285                     if (!var) {
00286                         ret = AVERROR(ENOMEM);
00287                         goto fail;
00288                     }
00289                 }
00290                 seg = av_malloc(sizeof(struct segment));
00291                 if (!seg) {
00292                     ret = AVERROR(ENOMEM);
00293                     goto fail;
00294                 }
00295                 seg->duration = duration;
00296                 seg->key_type = key_type;
00297                 if (has_iv) {
00298                     memcpy(seg->iv, iv, sizeof(iv));
00299                 } else {
00300                     int seq = var->start_seq_no + var->n_segments;
00301                     memset(seg->iv, 0, sizeof(seg->iv));
00302                     AV_WB32(seg->iv + 12, seq);
00303                 }
00304                 ff_make_absolute_url(seg->key, sizeof(seg->key), url, key);
00305                 ff_make_absolute_url(seg->url, sizeof(seg->url), url, line);
00306                 dynarray_add(&var->segments, &var->n_segments, seg);
00307                 is_segment = 0;
00308             }
00309         }
00310     }
00311     if (var)
00312         var->last_load_time = av_gettime();
00313 
00314 fail:
00315     if (close_in)
00316         avio_close(in);
00317     return ret;
00318 }
00319 
00320 static int open_input(struct variant *var)
00321 {
00322     struct segment *seg = var->segments[var->cur_seq_no - var->start_seq_no];
00323     if (seg->key_type == KEY_NONE) {
00324         return ffurl_open(&var->input, seg->url, AVIO_RDONLY);
00325     } else if (seg->key_type == KEY_AES_128) {
00326         char iv[33], key[33], url[MAX_URL_SIZE];
00327         int ret;
00328         if (strcmp(seg->key, var->key_url)) {
00329             URLContext *uc;
00330             if (ffurl_open(&uc, seg->key, AVIO_RDONLY) == 0) {
00331                 if (ffurl_read_complete(uc, var->key, sizeof(var->key))
00332                     != sizeof(var->key)) {
00333                     av_log(NULL, AV_LOG_ERROR, "Unable to read key file %s\n",
00334                            seg->key);
00335                 }
00336                 ffurl_close(uc);
00337             } else {
00338                 av_log(NULL, AV_LOG_ERROR, "Unable to open key file %s\n",
00339                        seg->key);
00340             }
00341             av_strlcpy(var->key_url, seg->key, sizeof(var->key_url));
00342         }
00343         ff_data_to_hex(iv, seg->iv, sizeof(seg->iv), 0);
00344         ff_data_to_hex(key, var->key, sizeof(var->key), 0);
00345         iv[32] = key[32] = '\0';
00346         if (strstr(seg->url, "://"))
00347             snprintf(url, sizeof(url), "crypto+%s", seg->url);
00348         else
00349             snprintf(url, sizeof(url), "crypto:%s", seg->url);
00350         if ((ret = ffurl_alloc(&var->input, url, AVIO_RDONLY)) < 0)
00351             return ret;
00352         av_set_string3(var->input->priv_data, "key", key, 0, NULL);
00353         av_set_string3(var->input->priv_data, "iv", iv, 0, NULL);
00354         if ((ret = ffurl_connect(var->input)) < 0) {
00355             ffurl_close(var->input);
00356             var->input = NULL;
00357             return ret;
00358         }
00359         return 0;
00360     }
00361     return AVERROR(ENOSYS);
00362 }
00363 
00364 static int read_data(void *opaque, uint8_t *buf, int buf_size)
00365 {
00366     struct variant *v = opaque;
00367     AppleHTTPContext *c = v->parent->priv_data;
00368     int ret, i;
00369 
00370 restart:
00371     if (!v->input) {
00372 reload:
00373         /* If this is a live stream and target_duration has elapsed since
00374          * the last playlist reload, reload the variant playlists now. */
00375         if (!v->finished &&
00376             av_gettime() - v->last_load_time >= v->target_duration*1000000 &&
00377             (ret = parse_playlist(c, v->url, v, NULL)) < 0)
00378                 return ret;
00379         if (v->cur_seq_no < v->start_seq_no) {
00380             av_log(NULL, AV_LOG_WARNING,
00381                    "skipping %d segments ahead, expired from playlists\n",
00382                    v->start_seq_no - v->cur_seq_no);
00383             v->cur_seq_no = v->start_seq_no;
00384         }
00385         if (v->cur_seq_no >= v->start_seq_no + v->n_segments) {
00386             if (v->finished)
00387                 return AVERROR_EOF;
00388             while (av_gettime() - v->last_load_time <
00389                    v->target_duration*1000000) {
00390                 if (url_interrupt_cb())
00391                     return AVERROR_EXIT;
00392                 usleep(100*1000);
00393             }
00394             /* Enough time has elapsed since the last reload */
00395             goto reload;
00396         }
00397 
00398         ret = ffurl_open(&v->input,
00399                          v->segments[v->cur_seq_no - v->start_seq_no]->url,
00400                          AVIO_RDONLY);
00401         if (ret < 0)
00402             return ret;
00403     }
00404     ret = ffurl_read(v->input, buf, buf_size);
00405     if (ret > 0)
00406         return ret;
00407     if (ret < 0 && ret != AVERROR_EOF)
00408         return ret;
00409     ffurl_close(v->input);
00410     v->input = NULL;
00411     v->cur_seq_no++;
00412 
00413     c->end_of_segment = 1;
00414     c->cur_seq_no = v->cur_seq_no;
00415 
00416     if (v->ctx) {
00417         v->needed = 0;
00418         for (i = v->stream_offset; i < v->stream_offset + v->ctx->nb_streams;
00419              i++) {
00420             if (v->parent->streams[i]->discard < AVDISCARD_ALL)
00421                 v->needed = 1;
00422         }
00423     }
00424     if (!v->needed) {
00425         av_log(v->parent, AV_LOG_INFO, "No longer receiving variant %d\n",
00426                v->index);
00427         return AVERROR_EOF;
00428     }
00429     goto restart;
00430 }
00431 
00432 static int applehttp_read_header(AVFormatContext *s, AVFormatParameters *ap)
00433 {
00434     AppleHTTPContext *c = s->priv_data;
00435     int ret = 0, i, j, stream_offset = 0;
00436 
00437     if ((ret = parse_playlist(c, s->filename, NULL, s->pb)) < 0)
00438         goto fail;
00439 
00440     if (c->n_variants == 0) {
00441         av_log(NULL, AV_LOG_WARNING, "Empty playlist\n");
00442         ret = AVERROR_EOF;
00443         goto fail;
00444     }
00445     /* If the playlist only contained variants, parse each individual
00446      * variant playlist. */
00447     if (c->n_variants > 1 || c->variants[0]->n_segments == 0) {
00448         for (i = 0; i < c->n_variants; i++) {
00449             struct variant *v = c->variants[i];
00450             if ((ret = parse_playlist(c, v->url, v, NULL)) < 0)
00451                 goto fail;
00452         }
00453     }
00454 
00455     if (c->variants[0]->n_segments == 0) {
00456         av_log(NULL, AV_LOG_WARNING, "Empty playlist\n");
00457         ret = AVERROR_EOF;
00458         goto fail;
00459     }
00460 
00461     /* If this isn't a live stream, calculate the total duration of the
00462      * stream. */
00463     if (c->variants[0]->finished) {
00464         int64_t duration = 0;
00465         for (i = 0; i < c->variants[0]->n_segments; i++)
00466             duration += c->variants[0]->segments[i]->duration;
00467         s->duration = duration * AV_TIME_BASE;
00468     }
00469 
00470     /* Open the demuxer for each variant */
00471     for (i = 0; i < c->n_variants; i++) {
00472         struct variant *v = c->variants[i];
00473         AVInputFormat *in_fmt = NULL;
00474         char bitrate_str[20];
00475         if (v->n_segments == 0)
00476             continue;
00477 
00478         if (!(v->ctx = avformat_alloc_context())) {
00479             ret = AVERROR(ENOMEM);
00480             goto fail;
00481         }
00482 
00483         v->index  = i;
00484         v->needed = 1;
00485         v->parent = s;
00486 
00487         /* If this is a live stream with more than 3 segments, start at the
00488          * third last segment. */
00489         v->cur_seq_no = v->start_seq_no;
00490         if (!v->finished && v->n_segments > 3)
00491             v->cur_seq_no = v->start_seq_no + v->n_segments - 3;
00492 
00493         v->read_buffer = av_malloc(INITIAL_BUFFER_SIZE);
00494         ffio_init_context(&v->pb, v->read_buffer, INITIAL_BUFFER_SIZE, 0, v,
00495                           read_data, NULL, NULL);
00496         v->pb.seekable = 0;
00497         ret = av_probe_input_buffer(&v->pb, &in_fmt, v->segments[0]->url,
00498                                     NULL, 0, 0);
00499         if (ret < 0)
00500             goto fail;
00501         v->ctx->pb       = &v->pb;
00502         ret = avformat_open_input(&v->ctx, v->segments[0]->url, in_fmt, NULL);
00503         if (ret < 0)
00504             goto fail;
00505         v->stream_offset = stream_offset;
00506         snprintf(bitrate_str, sizeof(bitrate_str), "%d", v->bandwidth);
00507         /* Create new AVStreams for each stream in this variant */
00508         for (j = 0; j < v->ctx->nb_streams; j++) {
00509             AVStream *st = av_new_stream(s, i);
00510             if (!st) {
00511                 ret = AVERROR(ENOMEM);
00512                 goto fail;
00513             }
00514             avcodec_copy_context(st->codec, v->ctx->streams[j]->codec);
00515             if (v->bandwidth)
00516                 av_dict_set(&st->metadata, "variant_bitrate", bitrate_str,
00517                                  0);
00518         }
00519         stream_offset += v->ctx->nb_streams;
00520     }
00521 
00522     c->first_packet = 1;
00523 
00524     return 0;
00525 fail:
00526     free_variant_list(c);
00527     return ret;
00528 }
00529 
00530 static int recheck_discard_flags(AVFormatContext *s, int first)
00531 {
00532     AppleHTTPContext *c = s->priv_data;
00533     int i, changed = 0;
00534 
00535     /* Check if any new streams are needed */
00536     for (i = 0; i < c->n_variants; i++)
00537         c->variants[i]->cur_needed = 0;;
00538 
00539     for (i = 0; i < s->nb_streams; i++) {
00540         AVStream *st = s->streams[i];
00541         struct variant *var = c->variants[s->streams[i]->id];
00542         if (st->discard < AVDISCARD_ALL)
00543             var->cur_needed = 1;
00544     }
00545     for (i = 0; i < c->n_variants; i++) {
00546         struct variant *v = c->variants[i];
00547         if (v->cur_needed && !v->needed) {
00548             v->needed = 1;
00549             changed = 1;
00550             v->cur_seq_no = c->cur_seq_no;
00551             v->pb.eof_reached = 0;
00552             av_log(s, AV_LOG_INFO, "Now receiving variant %d\n", i);
00553         } else if (first && !v->cur_needed && v->needed) {
00554             if (v->input)
00555                 ffurl_close(v->input);
00556             v->input = NULL;
00557             v->needed = 0;
00558             changed = 1;
00559             av_log(s, AV_LOG_INFO, "No longer receiving variant %d\n", i);
00560         }
00561     }
00562     return changed;
00563 }
00564 
00565 static int applehttp_read_packet(AVFormatContext *s, AVPacket *pkt)
00566 {
00567     AppleHTTPContext *c = s->priv_data;
00568     int ret, i, minvariant = -1;
00569 
00570     if (c->first_packet) {
00571         recheck_discard_flags(s, 1);
00572         c->first_packet = 0;
00573     }
00574 
00575 start:
00576     c->end_of_segment = 0;
00577     for (i = 0; i < c->n_variants; i++) {
00578         struct variant *var = c->variants[i];
00579         /* Make sure we've got one buffered packet from each open variant
00580          * stream */
00581         if (var->needed && !var->pkt.data) {
00582             ret = av_read_frame(var->ctx, &var->pkt);
00583             if (ret < 0) {
00584                 if (!url_feof(&var->pb))
00585                     return ret;
00586                 reset_packet(&var->pkt);
00587             }
00588         }
00589         /* Check if this stream has the packet with the lowest dts */
00590         if (var->pkt.data) {
00591             if (minvariant < 0 ||
00592                 var->pkt.dts < c->variants[minvariant]->pkt.dts)
00593                 minvariant = i;
00594         }
00595     }
00596     if (c->end_of_segment) {
00597         if (recheck_discard_flags(s, 0))
00598             goto start;
00599     }
00600     /* If we got a packet, return it */
00601     if (minvariant >= 0) {
00602         *pkt = c->variants[minvariant]->pkt;
00603         pkt->stream_index += c->variants[minvariant]->stream_offset;
00604         reset_packet(&c->variants[minvariant]->pkt);
00605         return 0;
00606     }
00607     return AVERROR_EOF;
00608 }
00609 
00610 static int applehttp_close(AVFormatContext *s)
00611 {
00612     AppleHTTPContext *c = s->priv_data;
00613 
00614     free_variant_list(c);
00615     return 0;
00616 }
00617 
00618 static int applehttp_read_seek(AVFormatContext *s, int stream_index,
00619                                int64_t timestamp, int flags)
00620 {
00621     AppleHTTPContext *c = s->priv_data;
00622     int i, j, ret;
00623 
00624     if ((flags & AVSEEK_FLAG_BYTE) || !c->variants[0]->finished)
00625         return AVERROR(ENOSYS);
00626 
00627     timestamp = av_rescale_rnd(timestamp, 1, stream_index >= 0 ?
00628                                s->streams[stream_index]->time_base.den :
00629                                AV_TIME_BASE, flags & AVSEEK_FLAG_BACKWARD ?
00630                                AV_ROUND_DOWN : AV_ROUND_UP);
00631     ret = AVERROR(EIO);
00632     for (i = 0; i < c->n_variants; i++) {
00633         /* Reset reading */
00634         struct variant *var = c->variants[i];
00635         int64_t pos = 0;
00636         if (var->input) {
00637             ffurl_close(var->input);
00638             var->input = NULL;
00639         }
00640         av_free_packet(&var->pkt);
00641         reset_packet(&var->pkt);
00642         var->pb.eof_reached = 0;
00643 
00644         /* Locate the segment that contains the target timestamp */
00645         for (j = 0; j < var->n_segments; j++) {
00646             if (timestamp >= pos &&
00647                 timestamp < pos + var->segments[j]->duration) {
00648                 var->cur_seq_no = var->start_seq_no + j;
00649                 ret = 0;
00650                 break;
00651             }
00652             pos += var->segments[j]->duration;
00653         }
00654     }
00655     return ret;
00656 }
00657 
00658 static int applehttp_probe(AVProbeData *p)
00659 {
00660     /* Require #EXTM3U at the start, and either one of the ones below
00661      * somewhere for a proper match. */
00662     if (strncmp(p->buf, "#EXTM3U", 7))
00663         return 0;
00664     if (strstr(p->buf, "#EXT-X-STREAM-INF:")     ||
00665         strstr(p->buf, "#EXT-X-TARGETDURATION:") ||
00666         strstr(p->buf, "#EXT-X-MEDIA-SEQUENCE:"))
00667         return AVPROBE_SCORE_MAX;
00668     return 0;
00669 }
00670 
00671 AVInputFormat ff_applehttp_demuxer = {
00672     "applehttp",
00673     NULL_IF_CONFIG_SMALL("Apple HTTP Live Streaming format"),
00674     sizeof(AppleHTTPContext),
00675     applehttp_probe,
00676     applehttp_read_header,
00677     applehttp_read_packet,
00678     applehttp_close,
00679     applehttp_read_seek,
00680 };

Generated on Fri Feb 22 2013 07:24:31 for FFmpeg by  doxygen 1.7.1