39 #define DEFAULT_APNG_FPS 15 77 if (bytestream2_get_be64(&gb) !=
PNGSIG)
81 len = bytestream2_get_be32(&gb);
85 tag = bytestream2_get_le32(&gb);
88 if (tag !=
MKTAG(
'I',
'D',
'A',
'T') &&
93 case MKTAG(
'I',
'H',
'D',
'R'):
101 case MKTAG(
'a',
'c',
'T',
'L'):
104 bytestream2_get_be32(&gb) == 0)
109 case MKTAG(
'I',
'D',
'A',
'T'):
130 if (previous_size > INT_MAX - len)
133 new_size = previous_size +
len;
143 return previous_size;
162 if (len != 13 || tag !=
MKTAG(
'I',
'H',
'D',
'R'))
192 if (acTL_found && ctx->
num_play != 1) {
198 }
else if (offset < 0) {
206 if ((ctx->
num_play == 1 || !acTL_found) &&
211 if (len > 0x7fffffff) {
218 case MKTAG(
'a',
'c',
'T',
'L'):
219 if ((ret =
avio_seek(pb, -8, SEEK_CUR)) < 0 ||
228 case MKTAG(
'f',
'c',
'T',
'L'):
233 if ((ret =
avio_seek(pb, -8, SEEK_CUR)) < 0)
237 if ((ret =
avio_seek(pb, -8, SEEK_CUR)) < 0 ||
253 uint32_t sequence_number,
width,
height, x_offset, y_offset;
254 uint16_t delay_num, delay_den;
271 if (!delay_num || (ctx->
max_fps && delay_den / delay_num > ctx->
max_fps)) {
280 "sequence_number: %"PRId32
", " 282 "height: %"PRIu32
", " 283 "x_offset: %"PRIu32
", " 284 "y_offset: %"PRIu32
", " 285 "delay_num: %"PRIu16
", " 286 "delay_den: %"PRIu16
", " 304 if (sequence_number == 0 ||
350 case MKTAG(
'f',
'c',
'T',
'L'):
360 if (len > 0x7fffffff ||
361 tag !=
MKTAG(
'f',
'd',
'A',
'T') &&
362 tag !=
MKTAG(
'I',
'D',
'A',
'T'))
365 size = 38 + 8 + len + 4 ;
369 if ((ret =
avio_seek(pb, -46, SEEK_CUR)) < 0 ||
379 tag !=
MKTAG(
'f',
'c',
'T',
'L') &&
380 tag !=
MKTAG(
'I',
'E',
'N',
'D')) {
381 if (len > 0x7fffffff)
383 if ((ret =
avio_seek(pb, -8, SEEK_CUR)) < 0 ||
391 if ((ret =
avio_seek(pb, -8, SEEK_CUR)) < 0)
399 case MKTAG(
'I',
'E',
'N',
'D'):
444 .priv_class = &demuxer_class,
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
int64_t avio_size(AVIOContext *s)
Get the filesize.
void * av_realloc(void *ptr, size_t size)
Allocate, reallocate, or free a block of memory.
#define AV_LOG_WARNING
Something somehow does not look correct.
#define LIBAVUTIL_VERSION_INT
#define avpriv_request_sample(...)
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
fseek() equivalent for AVIOContext.
const char * av_default_item_name(void *ptr)
Return the context name.
static av_always_inline void bytestream2_init(GetByteContext *g, const uint8_t *buf, int buf_size)
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
AVInputFormat ff_apng_demuxer
unsigned int avio_rb16(AVIOContext *s)
This struct describes the properties of an encoded stream.
const char * class_name
The name of the class; usually it is the same name as the context structure type to which the AVClass...
unsigned int avio_rb32(AVIOContext *s)
it s the only field you need to keep assuming you have a context There is some magic you don t need to care about around this just let it vf offset
static av_cold int end(AVCodecContext *avctx)
int64_t duration
Duration of this packet in AVStream->time_base units, 0 if unknown.
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_WL32 unsigned int_TMPL AV_WL24 unsigned int_TMPL AV_WL16 uint64_t_TMPL AV_WB64 unsigned int_TMPL AV_RB32
AVStream ** streams
A list of all streams in the file.
#define AVERROR_EOF
End of file.
uint64_t avio_rb64(AVIOContext *s)
static av_always_inline int64_t avio_tell(AVIOContext *s)
ftell() equivalent for AVIOContext.
int avio_read(AVIOContext *s, unsigned char *buf, int size)
Read size bytes from AVIOContext into buf.
#define AV_PKT_FLAG_KEY
The packet contains a keyframe.
int64_t av_rescale_q(int64_t a, AVRational bq, AVRational cq)
Rescale a 64-bit integer by 2 rational numbers.
unsigned int avio_rl32(AVIOContext *s)
static av_always_inline void bytestream2_skip(GetByteContext *g, unsigned int size)
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
#define AV_LOG_DEBUG
Stuff which is only useful for libav* developers.
#define av_fourcc2str(fourcc)
enum AVMediaType codec_type
General type of the encoded data.
static av_always_inline unsigned int bytestream2_get_bytes_left(GetByteContext *g)
int flags
A combination of AV_PKT_FLAG values.
int extradata_size
Size of the extradata content in bytes.
int avio_r8(AVIOContext *s)
int buf_size
Size of buf except extra allocated bytes.
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
int av_image_check_size(unsigned int w, unsigned int h, int log_offset, void *log_ctx)
Check if the given dimension of an image is valid, meaning that all bytes of the image can be address...
static int decode_fctl_chunk(AVFormatContext *s, APNGDemuxContext *ctx, AVPacket *pkt)
static int append_extradata(AVCodecParameters *par, AVIOContext *pb, int len)
static int apng_read_packet(AVFormatContext *s, AVPacket *pkt)
static int read_header(FFV1Context *f)
#define AVERROR_PATCHWELCOME
Not yet implemented in FFmpeg, patches welcome.
static int read_packet(void *opaque, uint8_t *buf, int buf_size)
AVIOContext * pb
I/O context.
Describe the class of an AVClass context structure.
Rational number (pair of numerator and denominator).
#define AV_OPT_FLAG_DECODING_PARAM
a generic parameter which can be set by the user for demuxing or decoding
static const AVOption options[]
This structure contains the data a format has to probe a file.
static const AVClass demuxer_class
#define flags(name, subs,...)
int ffio_ensure_seekback(AVIOContext *s, int64_t buf_size)
Ensures that the requested seekback buffer size will be available.
#define AV_INPUT_BUFFER_PADDING_SIZE
Required number of additionally allocated bytes at the end of the input bitstream for decoding...
void * priv_data
Format private data.
uint8_t * extradata
Extra binary data needed for initializing the decoder, codec-dependent.
int64_t dts
Decompression timestamp in AVStream->time_base units; the time at which the packet is decompressed...
AVCodecParameters * codecpar
Codec parameters associated with this stream.
int avio_feof(AVIOContext *s)
Similar to feof() but also returns nonzero on read errors.
static int apng_probe(const AVProbeData *p)
AVRational time_base
This is the fundamental unit of time (in seconds) in terms of which frame timestamps are represented...
Filter the word “frame” indicates either a video frame or a group of audio as stored in an AVFrame structure Format for each input and each output the list of supported formats For video that means pixel format For audio that means channel sample they are references to shared objects When the negotiation mechanism computes the intersection of the formats supported at each end of a all references to both lists are replaced with a reference to the intersection And when a single format is eventually chosen for a link amongst the remaining all references to the list are updated That means that if a filter requires that its input and output have the same format amongst a supported all it has to do is use a reference to the same list of formats query_formats can leave some formats unset and return AVERROR(EAGAIN) to cause the negotiation mechanism toagain later.That can be used by filters with complex requirements to use the format negotiated on one link to set the formats supported on another.Frame references ownership and permissions
#define MKTAG(a, b, c, d)
This structure stores compressed data.
static int apng_read_header(AVFormatContext *s)
int64_t pts
Presentation timestamp in AVStream->time_base units; the time at which the decompressed packet will b...
#define AV_NOPTS_VALUE
Undefined timestamp value.