Libav 0.7.1
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 Libav.
00006  *
00007  * Libav 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  * Libav 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 Libav; 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_FLAG_READ)) < 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 (!in->eof_reached) {
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_FLAG_READ);
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_FLAG_READ) == 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_FLAG_READ)) < 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 = open_input(v);
00399         if (ret < 0)
00400             return ret;
00401     }
00402     ret = ffurl_read(v->input, buf, buf_size);
00403     if (ret > 0)
00404         return ret;
00405     if (ret < 0 && ret != AVERROR_EOF)
00406         return ret;
00407     ffurl_close(v->input);
00408     v->input = NULL;
00409     v->cur_seq_no++;
00410 
00411     c->end_of_segment = 1;
00412     c->cur_seq_no = v->cur_seq_no;
00413 
00414     if (v->ctx) {
00415         v->needed = 0;
00416         for (i = v->stream_offset; i < v->stream_offset + v->ctx->nb_streams;
00417              i++) {
00418             if (v->parent->streams[i]->discard < AVDISCARD_ALL)
00419                 v->needed = 1;
00420         }
00421     }
00422     if (!v->needed) {
00423         av_log(v->parent, AV_LOG_INFO, "No longer receiving variant %d\n",
00424                v->index);
00425         return AVERROR_EOF;
00426     }
00427     goto restart;
00428 }
00429 
00430 static int applehttp_read_header(AVFormatContext *s, AVFormatParameters *ap)
00431 {
00432     AppleHTTPContext *c = s->priv_data;
00433     int ret = 0, i, j, stream_offset = 0;
00434 
00435     if ((ret = parse_playlist(c, s->filename, NULL, s->pb)) < 0)
00436         goto fail;
00437 
00438     if (c->n_variants == 0) {
00439         av_log(NULL, AV_LOG_WARNING, "Empty playlist\n");
00440         ret = AVERROR_EOF;
00441         goto fail;
00442     }
00443     /* If the playlist only contained variants, parse each individual
00444      * variant playlist. */
00445     if (c->n_variants > 1 || c->variants[0]->n_segments == 0) {
00446         for (i = 0; i < c->n_variants; i++) {
00447             struct variant *v = c->variants[i];
00448             if ((ret = parse_playlist(c, v->url, v, NULL)) < 0)
00449                 goto fail;
00450         }
00451     }
00452 
00453     if (c->variants[0]->n_segments == 0) {
00454         av_log(NULL, AV_LOG_WARNING, "Empty playlist\n");
00455         ret = AVERROR_EOF;
00456         goto fail;
00457     }
00458 
00459     /* If this isn't a live stream, calculate the total duration of the
00460      * stream. */
00461     if (c->variants[0]->finished) {
00462         int64_t duration = 0;
00463         for (i = 0; i < c->variants[0]->n_segments; i++)
00464             duration += c->variants[0]->segments[i]->duration;
00465         s->duration = duration * AV_TIME_BASE;
00466     }
00467 
00468     /* Open the demuxer for each variant */
00469     for (i = 0; i < c->n_variants; i++) {
00470         struct variant *v = c->variants[i];
00471         AVInputFormat *in_fmt = NULL;
00472         char bitrate_str[20];
00473         if (v->n_segments == 0)
00474             continue;
00475 
00476         if (!(v->ctx = avformat_alloc_context())) {
00477             ret = AVERROR(ENOMEM);
00478             goto fail;
00479         }
00480 
00481         v->index  = i;
00482         v->needed = 1;
00483         v->parent = s;
00484 
00485         /* If this is a live stream with more than 3 segments, start at the
00486          * third last segment. */
00487         v->cur_seq_no = v->start_seq_no;
00488         if (!v->finished && v->n_segments > 3)
00489             v->cur_seq_no = v->start_seq_no + v->n_segments - 3;
00490 
00491         v->read_buffer = av_malloc(INITIAL_BUFFER_SIZE);
00492         ffio_init_context(&v->pb, v->read_buffer, INITIAL_BUFFER_SIZE, 0, v,
00493                           read_data, NULL, NULL);
00494         v->pb.seekable = 0;
00495         ret = av_probe_input_buffer(&v->pb, &in_fmt, v->segments[0]->url,
00496                                     NULL, 0, 0);
00497         if (ret < 0)
00498             goto fail;
00499         v->ctx->pb       = &v->pb;
00500         ret = avformat_open_input(&v->ctx, v->segments[0]->url, in_fmt, NULL);
00501         if (ret < 0)
00502             goto fail;
00503         v->stream_offset = stream_offset;
00504         snprintf(bitrate_str, sizeof(bitrate_str), "%d", v->bandwidth);
00505         /* Create new AVStreams for each stream in this variant */
00506         for (j = 0; j < v->ctx->nb_streams; j++) {
00507             AVStream *st = av_new_stream(s, i);
00508             if (!st) {
00509                 ret = AVERROR(ENOMEM);
00510                 goto fail;
00511             }
00512             avcodec_copy_context(st->codec, v->ctx->streams[j]->codec);
00513             if (v->bandwidth)
00514                 av_dict_set(&st->metadata, "variant_bitrate", bitrate_str,
00515                                  0);
00516         }
00517         stream_offset += v->ctx->nb_streams;
00518     }
00519 
00520     c->first_packet = 1;
00521 
00522     return 0;
00523 fail:
00524     free_variant_list(c);
00525     return ret;
00526 }
00527 
00528 static int recheck_discard_flags(AVFormatContext *s, int first)
00529 {
00530     AppleHTTPContext *c = s->priv_data;
00531     int i, changed = 0;
00532 
00533     /* Check if any new streams are needed */
00534     for (i = 0; i < c->n_variants; i++)
00535         c->variants[i]->cur_needed = 0;;
00536 
00537     for (i = 0; i < s->nb_streams; i++) {
00538         AVStream *st = s->streams[i];
00539         struct variant *var = c->variants[s->streams[i]->id];
00540         if (st->discard < AVDISCARD_ALL)
00541             var->cur_needed = 1;
00542     }
00543     for (i = 0; i < c->n_variants; i++) {
00544         struct variant *v = c->variants[i];
00545         if (v->cur_needed && !v->needed) {
00546             v->needed = 1;
00547             changed = 1;
00548             v->cur_seq_no = c->cur_seq_no;
00549             v->pb.eof_reached = 0;
00550             av_log(s, AV_LOG_INFO, "Now receiving variant %d\n", i);
00551         } else if (first && !v->cur_needed && v->needed) {
00552             if (v->input)
00553                 ffurl_close(v->input);
00554             v->input = NULL;
00555             v->needed = 0;
00556             changed = 1;
00557             av_log(s, AV_LOG_INFO, "No longer receiving variant %d\n", i);
00558         }
00559     }
00560     return changed;
00561 }
00562 
00563 static int applehttp_read_packet(AVFormatContext *s, AVPacket *pkt)
00564 {
00565     AppleHTTPContext *c = s->priv_data;
00566     int ret, i, minvariant = -1;
00567 
00568     if (c->first_packet) {
00569         recheck_discard_flags(s, 1);
00570         c->first_packet = 0;
00571     }
00572 
00573 start:
00574     c->end_of_segment = 0;
00575     for (i = 0; i < c->n_variants; i++) {
00576         struct variant *var = c->variants[i];
00577         /* Make sure we've got one buffered packet from each open variant
00578          * stream */
00579         if (var->needed && !var->pkt.data) {
00580             ret = av_read_frame(var->ctx, &var->pkt);
00581             if (ret < 0) {
00582                 if (!var->pb.eof_reached)
00583                     return ret;
00584                 reset_packet(&var->pkt);
00585             }
00586         }
00587         /* Check if this stream has the packet with the lowest dts */
00588         if (var->pkt.data) {
00589             if (minvariant < 0 ||
00590                 var->pkt.dts < c->variants[minvariant]->pkt.dts)
00591                 minvariant = i;
00592         }
00593     }
00594     if (c->end_of_segment) {
00595         if (recheck_discard_flags(s, 0))
00596             goto start;
00597     }
00598     /* If we got a packet, return it */
00599     if (minvariant >= 0) {
00600         *pkt = c->variants[minvariant]->pkt;
00601         pkt->stream_index += c->variants[minvariant]->stream_offset;
00602         reset_packet(&c->variants[minvariant]->pkt);
00603         return 0;
00604     }
00605     return AVERROR_EOF;
00606 }
00607 
00608 static int applehttp_close(AVFormatContext *s)
00609 {
00610     AppleHTTPContext *c = s->priv_data;
00611 
00612     free_variant_list(c);
00613     return 0;
00614 }
00615 
00616 static int applehttp_read_seek(AVFormatContext *s, int stream_index,
00617                                int64_t timestamp, int flags)
00618 {
00619     AppleHTTPContext *c = s->priv_data;
00620     int i, j, ret;
00621 
00622     if ((flags & AVSEEK_FLAG_BYTE) || !c->variants[0]->finished)
00623         return AVERROR(ENOSYS);
00624 
00625     timestamp = av_rescale_rnd(timestamp, 1, stream_index >= 0 ?
00626                                s->streams[stream_index]->time_base.den :
00627                                AV_TIME_BASE, flags & AVSEEK_FLAG_BACKWARD ?
00628                                AV_ROUND_DOWN : AV_ROUND_UP);
00629     ret = AVERROR(EIO);
00630     for (i = 0; i < c->n_variants; i++) {
00631         /* Reset reading */
00632         struct variant *var = c->variants[i];
00633         int64_t pos = 0;
00634         if (var->input) {
00635             ffurl_close(var->input);
00636             var->input = NULL;
00637         }
00638         av_free_packet(&var->pkt);
00639         reset_packet(&var->pkt);
00640         var->pb.eof_reached = 0;
00641 
00642         /* Locate the segment that contains the target timestamp */
00643         for (j = 0; j < var->n_segments; j++) {
00644             if (timestamp >= pos &&
00645                 timestamp < pos + var->segments[j]->duration) {
00646                 var->cur_seq_no = var->start_seq_no + j;
00647                 ret = 0;
00648                 break;
00649             }
00650             pos += var->segments[j]->duration;
00651         }
00652     }
00653     return ret;
00654 }
00655 
00656 static int applehttp_probe(AVProbeData *p)
00657 {
00658     /* Require #EXTM3U at the start, and either one of the ones below
00659      * somewhere for a proper match. */
00660     if (strncmp(p->buf, "#EXTM3U", 7))
00661         return 0;
00662     if (strstr(p->buf, "#EXT-X-STREAM-INF:")     ||
00663         strstr(p->buf, "#EXT-X-TARGETDURATION:") ||
00664         strstr(p->buf, "#EXT-X-MEDIA-SEQUENCE:"))
00665         return AVPROBE_SCORE_MAX;
00666     return 0;
00667 }
00668 
00669 AVInputFormat ff_applehttp_demuxer = {
00670     "applehttp",
00671     NULL_IF_CONFIG_SMALL("Apple HTTP Live Streaming format"),
00672     sizeof(AppleHTTPContext),
00673     applehttp_probe,
00674     applehttp_read_header,
00675     applehttp_read_packet,
00676     applehttp_close,
00677     applehttp_read_seek,
00678 };