72 crc =
av_crc(crc_table, crc, tagbuf, 4);
75 crc =
av_crc(crc_table, crc, buf, length);
90 "APNG muxer supports only a single video APNG stream.\n");
98 "Last frame delay is too precise. Reducing to %d/%d (%f).\n",
128 if (side_data_size) {
141 av_log(format_context,
AV_LOG_INFO,
"Only a single frame so saving as a normal PNG.\n");
145 if (existing_acTL_chunk) {
146 uint8_t *chunk_after_acTL = existing_acTL_chunk +
AV_RB32(existing_acTL_chunk) + 12;
155 if (existing_fcTL_chunk) {
156 uint8_t *chunk_after_fcTL = existing_fcTL_chunk +
AV_RB32(existing_fcTL_chunk) + 12;
172 if (!existing_acTL_chunk) {
183 if (existing_fcTL_chunk) {
186 existing_fcTL_chunk += 8;
187 delay.
num =
AV_RB16(existing_fcTL_chunk + 20);
188 delay.
den =
AV_RB16(existing_fcTL_chunk + 22);
190 if (delay.
num == 0 && delay.
den == 0) {
194 if (!
av_reduce(&delay.
num, &delay.
den, delay_num_raw, delay_den_raw, USHRT_MAX) &&
197 "Frame rate is too high or specified too precisely. Unable to copy losslessly.\n");
280 #define OFFSET(x) offsetof(APNGMuxContext, x) 281 #define ENC AV_OPT_FLAG_ENCODING_PARAM 283 {
"plays",
"Number of times to play the output: 0 - infinite loop, 1 - no loop",
OFFSET(
plays),
300 .mime_type =
"image/png",
301 .extensions =
"apng",
309 .priv_class = &apng_muxer_class,
static void write_packet(OutputFile *of, AVPacket *pkt, OutputStream *ost, int unqueue)
void avio_wb64(AVIOContext *s, uint64_t val)
static int apng_write_trailer(AVFormatContext *format_context)
#define AV_LOG_WARNING
Something somehow does not look correct.
#define LIBAVUTIL_VERSION_INT
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
static const AVClass apng_muxer_class
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.
void * av_mallocz(size_t size)
Allocate a memory block with alignment suitable for all memory accesses (including vectors if availab...
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_WB32 unsigned int_TMPL AV_WB24 unsigned int_TMPL AV_RB16
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...
#define av_assert0(cond)
assert() equivalent, that is always enabled.
void av_packet_free(AVPacket **pkt)
Free the packet, if the packet is reference counted, it will be unreferenced first.
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.
Public header for CRC hash function implementation.
static int flush_packet(AVFormatContext *format_context, AVPacket *packet)
static void apng_write_chunk(AVIOContext *io_context, uint32_t tag, uint8_t *buf, size_t length)
static av_always_inline int64_t avio_tell(AVIOContext *s)
ftell() equivalent for AVIOContext.
int av_reduce(int *dst_num, int *dst_den, int64_t num, int64_t den, int64_t max)
Reduce a fraction.
void avio_write(AVIOContext *s, const unsigned char *buf, int size)
int av_packet_ref(AVPacket *dst, const AVPacket *src)
Setup a new reference to the data described by a given packet.
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
AVOutputFormat ff_apng_muxer
enum AVMediaType codec_type
General type of the encoded data.
simple assert() macros that are a bit more flexible than ISO C assert().
uint8_t * av_packet_get_side_data(const AVPacket *pkt, enum AVPacketSideDataType type, buffer_size_t *size)
int extradata_size
Size of the extradata content in bytes.
unsigned int nb_streams
Number of elements in AVFormatContext.streams.
int seekable
A combination of AVIO_SEEKABLE_ flags or 0 when the stream is not seekable.
static int write_trailer(AVFormatContext *s1)
uint32_t av_crc(const AVCRC *ctx, uint32_t crc, const uint8_t *buffer, size_t length)
Calculate the CRC of a block.
static uint8_t * apng_find_chunk(uint32_t tag, uint8_t *buf, size_t length)
#define AVIO_SEEKABLE_NORMAL
Seeking works like for a local file.
The AV_PKT_DATA_NEW_EXTRADATA is used to notify the codec or the format that the extradata buffer was...
#define AV_LOG_INFO
Standard information.
AVIOContext * pb
I/O context.
void av_packet_unref(AVPacket *pkt)
Wipe the packet.
Describe the class of an AVClass context structure.
static const AVOption options[]
Rational number (pair of numerator and denominator).
static int apng_write_packet(AVFormatContext *format_context, AVPacket *packet)
#define flags(name, subs,...)
const AVCRC * av_crc_get_table(AVCRCId crc_id)
Get an initialized standard CRC table.
#define MKBETAG(a, b, c, d)
#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.
AVPacket * av_packet_alloc(void)
Allocate an AVPacket and set its fields to default values.
static void write_header(FFV1Context *f)
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...
void avio_wb32(AVIOContext *s, unsigned int val)
AVCodecParameters * codecpar
Codec parameters associated with this stream.
static void apng_deinit(AVFormatContext *s)
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
This structure stores compressed data.
static int apng_write_header(AVFormatContext *format_context)