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70 if (
size < 2 * 64 * 4) {
74 for (
i = 0;
i < 64;
i++, buf += 4)
76 for (
i = 0;
i < 64;
i++, buf += 4)
88 for (
i = 0;
i < 64;
i++) {
109 if (buf_size > INT_MAX/8)
117 if (!
c->decomp_buf) {
119 "Can't allocate decompression buffer.\n");
134 const uint8_t *buf = avpkt->
data;
135 int buf_size = avpkt->
size;
137 int orig_size = buf_size;
144 NUV_UNCOMPRESSED =
'0',
146 NUV_RTJPEG_IN_LZO =
'2',
158 if (buf[0] ==
'D' && buf[1] ==
'R') {
170 if (buf_size < 12 || buf[0] !=
'V') {
176 case NUV_RTJPEG_IN_LZO:
179 if (
c->width < 16 ||
c->height < 16) {
192 case NUV_UNCOMPRESSED:
193 minsize =
c->width *
c->height * 3 / 2;
196 minsize =
c->width/16 * (
c->height/16) * 6;
201 case NUV_RTJPEG_IN_LZO:
207 if (buf_size < minsize / 4)
213 if (comptype == NUV_RTJPEG_IN_LZO || comptype == NUV_LZO) {
215 int inlen = buf_size;
224 if (
c->codec_frameheader) {
233 if (buf[0] !=
'V' &&
AV_RL16(&buf[4]) != 0x000c) {
244 buf_size = avpkt->
size;
252 if (size_change || keyframe) {
260 memset(
c->pic->data[0], 0, avctx->
height *
c->pic->linesize[0]);
261 memset(
c->pic->data[1], 0x80, avctx->
height *
c->pic->linesize[1] / 2);
262 memset(
c->pic->data[2], 0x80, avctx->
height *
c->pic->linesize[2] / 2);
273 case NUV_UNCOMPRESSED: {
277 height = buf_size /
c->width / 3 * 2;
283 case NUV_RTJPEG_IN_LZO:
290 memset(
c->pic->data[0], 0,
c->width *
c->height);
291 memset(
c->pic->data[1], 128,
c->width *
c->height / 4);
292 memset(
c->pic->data[2], 128,
c->width *
c->height / 4);
316 c->decomp_buf =
NULL;
#define FF_CODEC_CAP_INIT_CLEANUP
The codec allows calling the close function for deallocation even if the init function returned a fai...
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
void av_frame_free(AVFrame **frame)
Free the frame and any dynamically allocated objects in it, e.g.
static void copy_frame(AVFrame *f, const uint8_t *src, int width, int height)
copy frame data from buffer to AVFrame, handling stride.
This structure describes decoded (raw) audio or video data.
static int codec_reinit(AVCodecContext *avctx, int width, int height, int quality)
int ff_set_dimensions(AVCodecContext *s, int width, int height)
Check that the provided frame dimensions are valid and set them on the codec context.
trying all byte sequences megabyte in length and selecting the best looking sequence will yield cases to try But a word about quality
#define RTJPEG_HEADER_SIZE
AVCodec p
The public AVCodec.
static int decode_frame(AVCodecContext *avctx, AVFrame *picture, int *got_frame, AVPacket *avpkt)
AVFrame * av_frame_alloc(void)
Allocate an AVFrame and set its fields to default values.
void ff_rtjpeg_decode_init(RTJpegContext *c, int width, int height, const uint32_t *lquant, const uint32_t *cquant)
initialize an RTJpegContext, may be called multiple times
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
#define AV_FRAME_FLAG_KEY
A flag to mark frames that are keyframes.
#define FF_CODEC_DECODE_CB(func)
int(* init)(AVBSFContext *ctx)
static int get_quant(AVCodecContext *avctx, NuvContext *c, const uint8_t *buf, int size)
extract quantization tables from codec data into our context
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_WL32 unsigned int_TMPL AV_WL24 unsigned int_TMPL AV_RL16
unsigned char * decomp_buf
@ AV_PIX_FMT_YUV420P
planar YUV 4:2:0, 12bpp, (1 Cr & Cb sample per 2x2 Y samples)
#define CODEC_LONG_NAME(str)
and forward the result(frame or status change) to the corresponding input. If nothing is possible
const FFCodec ff_nuv_decoder
@ AV_PICTURE_TYPE_I
Intra.
int ff_rtjpeg_decode_frame_yuv420(RTJpegContext *c, AVFrame *f, const uint8_t *buf, int buf_size)
decode one rtjpeg YUV420 frame
Undefined Behavior In the C some operations are like signed integer dereferencing freed accessing outside allocated Undefined Behavior must not occur in a C it is not safe even if the output of undefined operations is unused The unsafety may seem nit picking but Optimizing compilers have in fact optimized code on the assumption that no undefined Behavior occurs Optimizing code based on wrong assumptions can and has in some cases lead to effects beyond the output of computations The signed integer overflow problem in speed critical code Code which is highly optimized and works with signed integers sometimes has the problem that often the output of the computation does not c
static av_cold int decode_end(AVCodecContext *avctx)
int av_lzo1x_decode(void *out, int *outlen, const void *in, int *inlen)
Decodes LZO 1x compressed data.
#define AV_CODEC_CAP_DR1
Codec uses get_buffer() or get_encode_buffer() for allocating buffers and supports custom allocators.
int av_image_fill_arrays(uint8_t *dst_data[4], int dst_linesize[4], const uint8_t *src, enum AVPixelFormat pix_fmt, int width, int height, int align)
Setup the data pointers and linesizes based on the specified image parameters and the provided array.
int av_frame_ref(AVFrame *dst, const AVFrame *src)
Set up a new reference to the data described by the source frame.
static void get_quant_quality(NuvContext *c, int quality)
set quantization tables from a quality value
#define i(width, name, range_min, range_max)
#define AV_LZO_OUTPUT_PADDING
uint8_t * extradata
some codecs need / can use extradata like Huffman tables.
const uint8_t ff_mjpeg_std_chrominance_quant_tbl[64]
void av_frame_unref(AVFrame *frame)
Unreference all the buffers referenced by frame and reset the frame fields.
void ff_rtjpeg_init(RTJpegContext *c, struct AVCodecContext *avctx)
const char * name
Name of the codec implementation.
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
int64_t frame_num
Frame counter, set by libavcodec.
int ff_reget_buffer(AVCodecContext *avctx, AVFrame *frame, int flags)
Identical in function to ff_get_buffer(), except it reuses the existing buffer if available.
#define AV_INPUT_BUFFER_PADDING_SIZE
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_RL32
const uint8_t ff_mjpeg_std_luminance_quant_tbl[64]
main external API structure.
static void av_image_copy2(uint8_t *const dst_data[4], const int dst_linesizes[4], uint8_t *const src_data[4], const int src_linesizes[4], enum AVPixelFormat pix_fmt, int width, int height)
Wrapper around av_image_copy() to workaround the limitation that the conversion from uint8_t * const ...
static void init_frame(FlacEncodeContext *s, int nb_samples)
@ AV_PICTURE_TYPE_P
Predicted.
unsigned int codec_tag
fourcc (LSB first, so "ABCD" -> ('D'<<24) + ('C'<<16) + ('B'<<8) + 'A').
This structure stores compressed data.
void av_fast_malloc(void *ptr, unsigned int *size, size_t min_size)
Allocate a buffer, reusing the given one if large enough.
static av_cold int decode_init(AVCodecContext *avctx)
int width
picture width / height.
#define flags(name, subs,...)
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
#define MKTAG(a, b, c, d)
#define FF_REGET_BUFFER_FLAG_READONLY
the returned buffer does not need to be writable