ffmpeg/libavformat/id3v2.c

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/*
* ID3v2 header parser
* Copyright (c) 2003 Fabrice Bellard
*
* This file is part of Libav.
*
* Libav 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.
*
* Libav 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 Libav; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include "libavutil/avstring.h"
#include "libavutil/dict.h"
#include "libavutil/intreadwrite.h"
#include "avio_internal.h"
#include "internal.h"
#include "id3v1.h"
#include "id3v2.h"
const AVMetadataConv ff_id3v2_34_metadata_conv[] = {
{ "TALB", "album" },
{ "TCOM", "composer" },
{ "TCON", "genre" },
{ "TCOP", "copyright" },
{ "TENC", "encoded_by" },
{ "TIT2", "title" },
{ "TLAN", "language" },
{ "TPE1", "artist" },
{ "TPE2", "album_artist" },
{ "TPE3", "performer" },
{ "TPOS", "disc" },
{ "TPUB", "publisher" },
{ "TRCK", "track" },
{ "TSSE", "encoder" },
{ 0 }
};
const AVMetadataConv ff_id3v2_4_metadata_conv[] = {
{ "TDRL", "date" },
{ "TDRC", "date" },
{ "TDEN", "creation_time" },
{ "TSOA", "album-sort" },
{ "TSOP", "artist-sort" },
{ "TSOT", "title-sort" },
{ 0 }
};
static const AVMetadataConv id3v2_2_metadata_conv[] = {
{ "TAL", "album" },
{ "TCO", "genre" },
{ "TT2", "title" },
{ "TEN", "encoded_by" },
{ "TP1", "artist" },
{ "TP2", "album_artist" },
{ "TP3", "performer" },
{ "TRK", "track" },
{ 0 }
};
const char ff_id3v2_tags[][4] = {
"TALB", "TBPM", "TCOM", "TCON", "TCOP", "TDLY", "TENC", "TEXT",
"TFLT", "TIT1", "TIT2", "TIT3", "TKEY", "TLAN", "TLEN", "TMED",
"TOAL", "TOFN", "TOLY", "TOPE", "TOWN", "TPE1", "TPE2", "TPE3",
"TPE4", "TPOS", "TPUB", "TRCK", "TRSN", "TRSO", "TSRC", "TSSE",
{ 0 },
};
const char ff_id3v2_4_tags[][4] = {
"TDEN", "TDOR", "TDRC", "TDRL", "TDTG", "TIPL", "TMCL", "TMOO",
"TPRO", "TSOA", "TSOP", "TSOT", "TSST",
{ 0 },
};
const char ff_id3v2_3_tags[][4] = {
"TDAT", "TIME", "TORY", "TRDA", "TSIZ", "TYER",
{ 0 },
};
const char *ff_id3v2_picture_types[21] = {
"Other",
"32x32 pixels 'file icon'",
"Other file icon",
"Cover (front)",
"Cover (back)",
"Leaflet page",
"Media (e.g. label side of CD)",
"Lead artist/lead performer/soloist",
"Artist/performer",
"Conductor",
"Band/Orchestra",
"Composer",
"Lyricist/text writer",
"Recording Location",
"During recording",
"During performance",
"Movie/video screen capture",
"A bright coloured fish",
"Illustration",
"Band/artist logotype",
"Publisher/Studio logotype",
};
const CodecMime ff_id3v2_mime_tags[] = {
{ "image/gif", AV_CODEC_ID_GIF },
{ "image/jpeg", AV_CODEC_ID_MJPEG },
{ "image/jpg", AV_CODEC_ID_MJPEG },
{ "image/png", AV_CODEC_ID_PNG },
{ "image/tiff", AV_CODEC_ID_TIFF },
{ "image/bmp", AV_CODEC_ID_BMP },
{ "JPG", AV_CODEC_ID_MJPEG }, /* ID3v2.2 */
{ "PNG", AV_CODEC_ID_PNG }, /* ID3v2.2 */
{ "", AV_CODEC_ID_NONE },
};
int ff_id3v2_match(const uint8_t *buf, const char *magic)
{
return buf[0] == magic[0] &&
buf[1] == magic[1] &&
buf[2] == magic[2] &&
buf[3] != 0xff &&
buf[4] != 0xff &&
(buf[6] & 0x80) == 0 &&
(buf[7] & 0x80) == 0 &&
(buf[8] & 0x80) == 0 &&
(buf[9] & 0x80) == 0;
}
int ff_id3v2_tag_len(const uint8_t *buf)
{
int len = ((buf[6] & 0x7f) << 21) +
((buf[7] & 0x7f) << 14) +
((buf[8] & 0x7f) << 7) +
(buf[9] & 0x7f) +
ID3v2_HEADER_SIZE;
if (buf[5] & 0x10)
len += ID3v2_HEADER_SIZE;
return len;
}
static unsigned int get_size(AVIOContext *s, int len)
{
int v = 0;
while (len--)
v = (v << 7) + (avio_r8(s) & 0x7F);
return v;
}
/**
* Free GEOB type extra metadata.
*/
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static void free_geobtag(void *obj)
{
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ID3v2ExtraMetaGEOB *geob = obj;
av_free(geob->mime_type);
av_free(geob->file_name);
av_free(geob->description);
av_free(geob->data);
av_free(geob);
}
/**
* Decode characters to UTF-8 according to encoding type. The decoded buffer is
* always null terminated. Stop reading when either *maxread bytes are read from
* pb or U+0000 character is found.
*
* @param dst Pointer where the address of the buffer with the decoded bytes is
* stored. Buffer must be freed by caller.
* @param maxread Pointer to maximum number of characters to read from the
* AVIOContext. After execution the value is decremented by the number of bytes
* actually read.
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* @returns 0 if no error occurred, dst is uninitialized on error
*/
static int decode_str(AVFormatContext *s, AVIOContext *pb, int encoding,
uint8_t **dst, int *maxread)
{
int ret;
uint8_t tmp;
uint32_t ch = 1;
int left = *maxread;
unsigned int (*get)(AVIOContext*) = avio_rb16;
AVIOContext *dynbuf;
if ((ret = avio_open_dyn_buf(&dynbuf)) < 0) {
av_log(s, AV_LOG_ERROR, "Error opening memory stream\n");
return ret;
}
switch (encoding) {
case ID3v2_ENCODING_ISO8859:
while (left && ch) {
ch = avio_r8(pb);
PUT_UTF8(ch, tmp, avio_w8(dynbuf, tmp);)
left--;
}
break;
case ID3v2_ENCODING_UTF16BOM:
if ((left -= 2) < 0) {
av_log(s, AV_LOG_ERROR, "Cannot read BOM value, input too short\n");
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avio_close_dyn_buf(dynbuf, dst);
av_freep(dst);
return AVERROR_INVALIDDATA;
}
switch (avio_rb16(pb)) {
case 0xfffe:
get = avio_rl16;
case 0xfeff:
break;
default:
av_log(s, AV_LOG_ERROR, "Incorrect BOM value\n");
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avio_close_dyn_buf(dynbuf, dst);
av_freep(dst);
*maxread = left;
return AVERROR_INVALIDDATA;
}
// fall-through
case ID3v2_ENCODING_UTF16BE:
while ((left > 1) && ch) {
GET_UTF16(ch, ((left -= 2) >= 0 ? get(pb) : 0), break;)
PUT_UTF8(ch, tmp, avio_w8(dynbuf, tmp);)
}
if (left < 0)
left += 2; /* did not read last char from pb */
break;
case ID3v2_ENCODING_UTF8:
while (left && ch) {
ch = avio_r8(pb);
avio_w8(dynbuf, ch);
left--;
}
break;
default:
av_log(s, AV_LOG_WARNING, "Unknown encoding\n");
}
if (ch)
avio_w8(dynbuf, 0);
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avio_close_dyn_buf(dynbuf, dst);
*maxread = left;
return 0;
}
/**
* Parse a text tag.
*/
static void read_ttag(AVFormatContext *s, AVIOContext *pb, int taglen,
const char *key)
{
uint8_t *dst;
int encoding, dict_flags = AV_DICT_DONT_OVERWRITE | AV_DICT_DONT_STRDUP_VAL;
unsigned genre;
if (taglen < 1)
return;
encoding = avio_r8(pb);
taglen--; /* account for encoding type byte */
if (decode_str(s, pb, encoding, &dst, &taglen) < 0) {
av_log(s, AV_LOG_ERROR, "Error reading frame %s, skipped\n", key);
return;
}
if (!(strcmp(key, "TCON") && strcmp(key, "TCO")) &&
(sscanf(dst, "(%d)", &genre) == 1 || sscanf(dst, "%d", &genre) == 1) &&
genre <= ID3v1_GENRE_MAX) {
av_freep(&dst);
dst = av_strdup(ff_id3v1_genre_str[genre]);
} else if (!(strcmp(key, "TXXX") && strcmp(key, "TXX"))) {
/* dst now contains the key, need to get value */
key = dst;
if (decode_str(s, pb, encoding, &dst, &taglen) < 0) {
av_log(s, AV_LOG_ERROR, "Error reading frame %s, skipped\n", key);
av_freep(&key);
return;
}
dict_flags |= AV_DICT_DONT_STRDUP_KEY;
} else if (!*dst)
av_freep(&dst);
if (dst)
av_dict_set(&s->metadata, key, dst, dict_flags);
}
/**
* Parse GEOB tag into a ID3v2ExtraMetaGEOB struct.
*/
static void read_geobtag(AVFormatContext *s, AVIOContext *pb, int taglen,
char *tag, ID3v2ExtraMeta **extra_meta)
{
ID3v2ExtraMetaGEOB *geob_data = NULL;
ID3v2ExtraMeta *new_extra = NULL;
char encoding;
unsigned int len;
if (taglen < 1)
return;
geob_data = av_mallocz(sizeof(ID3v2ExtraMetaGEOB));
if (!geob_data) {
av_log(s, AV_LOG_ERROR, "Failed to alloc %zu bytes\n",
sizeof(ID3v2ExtraMetaGEOB));
return;
}
new_extra = av_mallocz(sizeof(ID3v2ExtraMeta));
if (!new_extra) {
av_log(s, AV_LOG_ERROR, "Failed to alloc %zu bytes\n",
sizeof(ID3v2ExtraMeta));
goto fail;
}
/* read encoding type byte */
encoding = avio_r8(pb);
taglen--;
/* read MIME type (always ISO-8859) */
if (decode_str(s, pb, ID3v2_ENCODING_ISO8859, &geob_data->mime_type,
&taglen) < 0 ||
taglen <= 0)
goto fail;
/* read file name */
if (decode_str(s, pb, encoding, &geob_data->file_name, &taglen) < 0 ||
taglen <= 0)
goto fail;
/* read content description */
if (decode_str(s, pb, encoding, &geob_data->description, &taglen) < 0 ||
taglen < 0)
goto fail;
if (taglen) {
/* save encapsulated binary data */
geob_data->data = av_malloc(taglen);
if (!geob_data->data) {
av_log(s, AV_LOG_ERROR, "Failed to alloc %d bytes\n", taglen);
goto fail;
}
if ((len = avio_read(pb, geob_data->data, taglen)) < taglen)
av_log(s, AV_LOG_WARNING,
"Error reading GEOB frame, data truncated.\n");
geob_data->datasize = len;
} else {
geob_data->data = NULL;
geob_data->datasize = 0;
}
/* add data to the list */
new_extra->tag = "GEOB";
new_extra->data = geob_data;
new_extra->next = *extra_meta;
*extra_meta = new_extra;
return;
fail:
av_log(s, AV_LOG_ERROR, "Error reading frame %s, skipped\n", tag);
free_geobtag(geob_data);
av_free(new_extra);
return;
}
static int is_number(const char *str)
{
while (*str >= '0' && *str <= '9')
str++;
return !*str;
}
static AVDictionaryEntry *get_date_tag(AVDictionary *m, const char *tag)
{
AVDictionaryEntry *t;
if ((t = av_dict_get(m, tag, NULL, AV_DICT_MATCH_CASE)) &&
strlen(t->value) == 4 && is_number(t->value))
return t;
return NULL;
}
static void merge_date(AVDictionary **m)
{
AVDictionaryEntry *t;
char date[17] = { 0 }; // YYYY-MM-DD hh:mm
if (!(t = get_date_tag(*m, "TYER")) &&
!(t = get_date_tag(*m, "TYE")))
return;
av_strlcpy(date, t->value, 5);
av_dict_set(m, "TYER", NULL, 0);
av_dict_set(m, "TYE", NULL, 0);
if (!(t = get_date_tag(*m, "TDAT")) &&
!(t = get_date_tag(*m, "TDA")))
goto finish;
snprintf(date + 4, sizeof(date) - 4, "-%.2s-%.2s", t->value + 2, t->value);
av_dict_set(m, "TDAT", NULL, 0);
av_dict_set(m, "TDA", NULL, 0);
if (!(t = get_date_tag(*m, "TIME")) &&
!(t = get_date_tag(*m, "TIM")))
goto finish;
snprintf(date + 10, sizeof(date) - 10,
" %.2s:%.2s", t->value, t->value + 2);
av_dict_set(m, "TIME", NULL, 0);
av_dict_set(m, "TIM", NULL, 0);
finish:
if (date[0])
av_dict_set(m, "date", date, 0);
}
static void free_apic(void *obj)
{
ID3v2ExtraMetaAPIC *apic = obj;
av_buffer_unref(&apic->buf);
av_freep(&apic->description);
av_freep(&apic);
}
static void read_apic(AVFormatContext *s, AVIOContext *pb, int taglen,
char *tag, ID3v2ExtraMeta **extra_meta)
{
int enc, pic_type;
char mimetype[64];
const CodecMime *mime = ff_id3v2_mime_tags;
enum AVCodecID id = AV_CODEC_ID_NONE;
ID3v2ExtraMetaAPIC *apic = NULL;
ID3v2ExtraMeta *new_extra = NULL;
int64_t end = avio_tell(pb) + taglen;
if (taglen <= 4)
goto fail;
new_extra = av_mallocz(sizeof(*new_extra));
apic = av_mallocz(sizeof(*apic));
if (!new_extra || !apic)
goto fail;
enc = avio_r8(pb);
taglen--;
/* mimetype */
taglen -= avio_get_str(pb, taglen, mimetype, sizeof(mimetype));
while (mime->id != AV_CODEC_ID_NONE) {
if (!av_strncasecmp(mime->str, mimetype, sizeof(mimetype))) {
id = mime->id;
break;
}
mime++;
}
if (id == AV_CODEC_ID_NONE) {
av_log(s, AV_LOG_WARNING,
"Unknown attached picture mimetype: %s, skipping.\n", mimetype);
goto fail;
}
apic->id = id;
/* picture type */
pic_type = avio_r8(pb);
taglen--;
if (pic_type < 0 || pic_type >= FF_ARRAY_ELEMS(ff_id3v2_picture_types)) {
av_log(s, AV_LOG_WARNING, "Unknown attached picture type %d.\n",
pic_type);
pic_type = 0;
}
apic->type = ff_id3v2_picture_types[pic_type];
/* description and picture data */
if (decode_str(s, pb, enc, &apic->description, &taglen) < 0) {
av_log(s, AV_LOG_ERROR,
"Error decoding attached picture description.\n");
goto fail;
}
apic->buf = av_buffer_alloc(taglen + FF_INPUT_BUFFER_PADDING_SIZE);
if (!apic->buf || avio_read(pb, apic->buf->data, taglen) != taglen)
goto fail;
memset(apic->buf->data + taglen, 0, FF_INPUT_BUFFER_PADDING_SIZE);
new_extra->tag = "APIC";
new_extra->data = apic;
new_extra->next = *extra_meta;
*extra_meta = new_extra;
return;
fail:
if (apic)
free_apic(apic);
av_freep(&new_extra);
avio_seek(pb, end, SEEK_SET);
}
typedef struct ID3v2EMFunc {
const char *tag3;
const char *tag4;
void (*read)(AVFormatContext *, AVIOContext *, int, char *,
ID3v2ExtraMeta **);
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void (*free)(void *obj);
} ID3v2EMFunc;
static const ID3v2EMFunc id3v2_extra_meta_funcs[] = {
{ "GEO", "GEOB", read_geobtag, free_geobtag },
{ "PIC", "APIC", read_apic, free_apic },
{ NULL }
};
/**
* Get the corresponding ID3v2EMFunc struct for a tag.
* @param isv34 Determines if v2.2 or v2.3/4 strings are used
* @return A pointer to the ID3v2EMFunc struct if found, NULL otherwise.
*/
static const ID3v2EMFunc *get_extra_meta_func(const char *tag, int isv34)
{
int i = 0;
while (id3v2_extra_meta_funcs[i].tag3) {
if (!memcmp(tag,
(isv34 ? id3v2_extra_meta_funcs[i].tag4 :
id3v2_extra_meta_funcs[i].tag3),
(isv34 ? 4 : 3)))
return &id3v2_extra_meta_funcs[i];
i++;
}
return NULL;
}
static void id3v2_parse(AVFormatContext *s, int len, uint8_t version,
uint8_t flags, ID3v2ExtraMeta **extra_meta)
{
int isv34, tlen, unsync;
char tag[5];
int64_t next, end = avio_tell(s->pb) + len;
int taghdrlen;
const char *reason = NULL;
AVIOContext pb;
AVIOContext *pbx;
unsigned char *buffer = NULL;
int buffer_size = 0;
const ID3v2EMFunc *extra_func;
switch (version) {
case 2:
if (flags & 0x40) {
reason = "compression";
goto error;
}
isv34 = 0;
taghdrlen = 6;
break;
case 3:
case 4:
isv34 = 1;
taghdrlen = 10;
break;
default:
reason = "version";
goto error;
}
unsync = flags & 0x80;
if (isv34 && flags & 0x40) { /* Extended header present, just skip over it */
int extlen = get_size(s->pb, 4);
if (version == 4)
/* In v2.4 the length includes the length field we just read. */
extlen -= 4;
if (extlen < 0) {
reason = "invalid extended header length";
goto error;
}
avio_skip(s->pb, extlen);
}
while (len >= taghdrlen) {
unsigned int tflags = 0;
int tunsync = 0;
if (isv34) {
avio_read(s->pb, tag, 4);
tag[4] = 0;
if (version == 3) {
tlen = avio_rb32(s->pb);
} else
tlen = get_size(s->pb, 4);
tflags = avio_rb16(s->pb);
tunsync = tflags & ID3v2_FLAG_UNSYNCH;
} else {
avio_read(s->pb, tag, 3);
tag[3] = 0;
tlen = avio_rb24(s->pb);
}
if (tlen < 0 || tlen > len - taghdrlen) {
av_log(s, AV_LOG_WARNING,
"Invalid size in frame %s, skipping the rest of tag.\n",
tag);
break;
}
len -= taghdrlen + tlen;
next = avio_tell(s->pb) + tlen;
if (!tlen) {
if (tag[0])
av_log(s, AV_LOG_DEBUG, "Invalid empty frame %s, skipping.\n",
tag);
continue;
}
if (tflags & ID3v2_FLAG_DATALEN) {
avio_rb32(s->pb);
tlen -= 4;
}
if (tflags & (ID3v2_FLAG_ENCRYPTION | ID3v2_FLAG_COMPRESSION)) {
av_log(s, AV_LOG_WARNING,
"Skipping encrypted/compressed ID3v2 frame %s.\n", tag);
avio_skip(s->pb, tlen);
/* check for text tag or supported special meta tag */
} else if (tag[0] == 'T' ||
(extra_meta &&
(extra_func = get_extra_meta_func(tag, isv34)))) {
if (unsync || tunsync) {
int64_t end = avio_tell(s->pb) + tlen;
uint8_t *b;
av_fast_malloc(&buffer, &buffer_size, tlen);
if (!buffer) {
av_log(s, AV_LOG_ERROR, "Failed to alloc %d bytes\n", tlen);
goto seek;
}
b = buffer;
while (avio_tell(s->pb) < end && !s->pb->eof_reached) {
*b++ = avio_r8(s->pb);
if (*(b - 1) == 0xff && avio_tell(s->pb) < end - 1 &&
!s->pb->eof_reached ) {
uint8_t val = avio_r8(s->pb);
*b++ = val ? val : avio_r8(s->pb);
}
}
ffio_init_context(&pb, buffer, b - buffer, 0, NULL, NULL, NULL,
NULL);
tlen = b - buffer;
pbx = &pb; // read from sync buffer
} else {
pbx = s->pb; // read straight from input
}
if (tag[0] == 'T')
/* parse text tag */
read_ttag(s, pbx, tlen, tag);
else
/* parse special meta tag */
extra_func->read(s, pbx, tlen, tag, extra_meta);
} else if (!tag[0]) {
if (tag[1])
av_log(s, AV_LOG_WARNING, "invalid frame id, assuming padding");
avio_skip(s->pb, tlen);
break;
}
/* Skip to end of tag */
seek:
avio_seek(s->pb, next, SEEK_SET);
}
/* Footer preset, always 10 bytes, skip over it */
if (version == 4 && flags & 0x10)
end += 10;
error:
if (reason)
av_log(s, AV_LOG_INFO, "ID3v2.%d tag skipped, cannot handle %s\n",
version, reason);
avio_seek(s->pb, end, SEEK_SET);
av_free(buffer);
return;
}
void ff_id3v2_read(AVFormatContext *s, const char *magic,
ID3v2ExtraMeta **extra_meta)
{
int len, ret;
uint8_t buf[ID3v2_HEADER_SIZE];
int found_header;
int64_t off;
do {
/* save the current offset in case there's nothing to read/skip */
off = avio_tell(s->pb);
ret = avio_read(s->pb, buf, ID3v2_HEADER_SIZE);
if (ret != ID3v2_HEADER_SIZE)
break;
found_header = ff_id3v2_match(buf, magic);
if (found_header) {
/* parse ID3v2 header */
len = ((buf[6] & 0x7f) << 21) |
((buf[7] & 0x7f) << 14) |
((buf[8] & 0x7f) << 7) |
(buf[9] & 0x7f);
id3v2_parse(s, len, buf[3], buf[5], extra_meta);
} else {
avio_seek(s->pb, off, SEEK_SET);
}
} while (found_header);
ff_metadata_conv(&s->metadata, NULL, ff_id3v2_34_metadata_conv);
ff_metadata_conv(&s->metadata, NULL, id3v2_2_metadata_conv);
ff_metadata_conv(&s->metadata, NULL, ff_id3v2_4_metadata_conv);
merge_date(&s->metadata);
}
void ff_id3v2_free_extra_meta(ID3v2ExtraMeta **extra_meta)
{
ID3v2ExtraMeta *current = *extra_meta, *next;
const ID3v2EMFunc *extra_func;
while (current) {
if ((extra_func = get_extra_meta_func(current->tag, 1)))
extra_func->free(current->data);
next = current->next;
av_freep(&current);
current = next;
}
}
int ff_id3v2_parse_apic(AVFormatContext *s, ID3v2ExtraMeta **extra_meta)
{
ID3v2ExtraMeta *cur;
for (cur = *extra_meta; cur; cur = cur->next) {
ID3v2ExtraMetaAPIC *apic;
AVStream *st;
if (strcmp(cur->tag, "APIC"))
continue;
apic = cur->data;
if (!(st = avformat_new_stream(s, NULL)))
return AVERROR(ENOMEM);
st->disposition |= AV_DISPOSITION_ATTACHED_PIC;
st->codec->codec_type = AVMEDIA_TYPE_VIDEO;
st->codec->codec_id = apic->id;
av_dict_set(&st->metadata, "title", apic->description, 0);
av_dict_set(&st->metadata, "comment", apic->type, 0);
av_init_packet(&st->attached_pic);
st->attached_pic.buf = apic->buf;
st->attached_pic.data = apic->buf->data;
st->attached_pic.size = apic->buf->size - FF_INPUT_BUFFER_PADDING_SIZE;
st->attached_pic.stream_index = st->index;
st->attached_pic.flags |= AV_PKT_FLAG_KEY;
apic->buf = NULL;
}
return 0;
}