66 #define GIF_DEFAULT_DELAY 10 70 #define GIF_MIN_DELAY 2 88 for (i = 0; i < 6; i++) {
100 int sb_size,
ret = 0;
102 while (0x00 != (sb_size =
avio_r8(pb))) {
118 if ((ret =
resync(pb)) < 0)
128 if (width == 0 || height == 0)
136 avio_skip(pb, 3 * (1 << ((flags & 0x07) + 1)));
148 while ((block_size =
avio_r8(pb)) != 0) {
156 if (block_size == 4) {
177 avio_skip(pb, 3 * (1 << ((flags & 0x07) + 1)));
212 int sb_size, ext_label =
avio_r8(pb);
216 if ((sb_size =
avio_r8(pb)) < 4) {
232 if ((ret =
avio_skip(pb, sb_size - 3)) < 0 )
239 if (ret < 0 || !sb_size)
245 if (ret < 0 || !sb_size)
248 if (sb_size == 3 && data[0] == 1) {
267 int packed_fields, block_label, ct_size,
268 keyframe, frame_parsed = 0,
ret;
270 unsigned char buf[6];
275 }
else if (
ret < 0) {
294 if (packed_fields & 0x80) {
295 ct_size = 3 * (1 << ((packed_fields & 0x07) + 1));
317 if (packed_fields & 0x80) {
318 ct_size = 3 * (1 << ((packed_fields & 0x07) + 1));
335 if (
avio_seek(pb, frame_start, SEEK_SET) != frame_start)
386 {
"max_gif_delay",
"maximum valid delay between frames (in hundredths of seconds)", offsetof(
GIFDemuxContext,
max_delay) ,
AV_OPT_TYPE_INT, {.i64 = 65535} , 0, 65535 , AV_OPT_FLAG_DECODING_PARAM },
408 .priv_class = &demuxer_class,
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
ptrdiff_t const GLvoid * data
#define LIBAVUTIL_VERSION_INT
AVRational sample_aspect_ratio
Video only.
int avio_read_to_bprint(AVIOContext *h, struct AVBPrint *pb, size_t max_size)
Read contents of h into print buffer, up to max_size bytes, or up to EOF.
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 const uint8_t gif87a_sig[6]
#define GIF_GCE_EXT_LABEL
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_WL32 unsigned int_TMPL AV_WL24 unsigned int_TMPL AV_RL16
int av_bprint_finalize(AVBPrint *buf, char **ret_str)
Finalize a print buffer.
const char * class_name
The name of the class; usually it is the same name as the context structure type to which the AVClass...
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.
AVStream ** streams
A list of all streams in the file.
#define AVERROR_EOF
End of file.
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.
#define GIF_COM_EXT_LABEL
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
AVDictionary * metadata
Metadata that applies to the whole file.
#define AV_BPRINT_SIZE_UNLIMITED
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
void av_bprint_init(AVBPrint *buf, unsigned size_init, unsigned size_max)
enum AVMediaType codec_type
General type of the encoded data.
int flags
A combination of AV_PKT_FLAG values.
int avio_r8(AVIOContext *s)
static void frame_end(MpegEncContext *s)
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
#define GIF_IMAGE_SEPARATOR
int min_delay
Minimum allowed delay between frames in hundredths of second.
#define GIF_APP_EXT_LABEL
#define GIF_EXTENSION_INTRODUCER
static int read_header(FFV1Context *f)
static int read_packet(void *opaque, uint8_t *buf, int buf_size)
AVIOContext * pb
I/O context.
static int frame_start(MpegEncContext *s)
int total_iter
loop options
int av_dict_set(AVDictionary **pm, const char *key, const char *value, int flags)
Set the given entry in *pm, overwriting an existing entry.
Describe the class of an AVClass context structure.
Rational number (pair of numerator and denominator).
int delay
Time span in hundredths of second before the next frame should be drawn on screen.
#define AV_OPT_FLAG_DECODING_PARAM
a generic parameter which can be set by the user for demuxing or decoding
This structure contains the data a format has to probe a file.
#define flags(name, subs,...)
int64_t duration
Decoding: duration of the stream, in stream time base.
unsigned int avio_rl16(AVIOContext *s)
int64_t start_time
Decoding: pts of the first frame of the stream in presentation order, in stream time base...
static const uint8_t gif89a_sig[6]
int64_t nb_frames
number of frames in this stream if known or 0
void * priv_data
Format private data.
#define AV_LOG_FATAL
Something went wrong and recovery is not possible.
AVCodecParameters * codecpar
Codec parameters associated with this stream.
int avio_feof(AVIOContext *s)
Similar to feof() but also returns nonzero on read errors.
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
AVRational r_frame_rate
Real base framerate of the stream.
This structure stores compressed data.