55 const uint8_t *bytestream_end = bytestream + avpkt->
size;
68 for (i = 0; i < 16; i++) {
69 a->
delta[
i] = *bytestream++;
73 for (y = 0; y < avctx->
height; y++) {
83 for (i = 0; i < 4; i++)
84 a->
offset[i] = *bytestream++;
86 offset = a->
offset[0] - a->
delta[bytestream[2] & 0xF];
87 for (x = 0; x < avctx->
width; x += 4) {
88 luma[0] = offset += a->
delta[bytestream[2] & 0xF];
89 luma[1] = offset += a->
delta[bytestream[2] >> 4];
90 luma[2] = offset += a->
delta[bytestream[0] & 0xF];
91 luma[3] = offset += a->
delta[bytestream[0] >> 4];
94 *cb++ = bytestream[3];
95 *
cr++ = bytestream[1];
102 offset = a->
offset[y & 3] - a->
delta[bytestream[2] & 0xF];
104 for (x = 0; x < avctx->
width; x += 8) {
105 luma[0] = offset += a->
delta[bytestream[2] & 0xF];
106 luma[1] = offset += a->
delta[bytestream[2] >> 4];
107 luma[2] = offset += a->
delta[bytestream[3] & 0xF];
108 luma[3] = offset += a->
delta[bytestream[3] >> 4];
109 luma[4] = offset += a->
delta[bytestream[0] & 0xF];
110 luma[5] = offset += a->
delta[bytestream[0] >> 4];
111 luma[6] = offset += a->
delta[bytestream[1] & 0xF];
112 luma[7] = offset += a->
delta[bytestream[1] >> 4];
121 return bytestream - avpkt->
data;
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
This structure describes decoded (raw) audio or video data.
ptrdiff_t const GLvoid * data
static av_cold int init(AVCodecContext *avctx)
#define avpriv_request_sample(...)
static av_cold int vcr1_decode_init(AVCodecContext *avctx)
The reader does not expect b to be semantically here and if the code is changed by maybe adding a a division or other the signedness will almost certainly be mistaken To avoid this confusion a new type was SUINT is the C unsigned type but it holds a signed int to use the same example SUINT a
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
static void decode(AVCodecContext *dec_ctx, AVPacket *pkt, AVFrame *frame, FILE *outfile)
#define av_assert0(cond)
assert() equivalent, that is always enabled.
static double cb(void *priv, double x, double y)
#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. ...
simple assert() macros that are a bit more flexible than ISO C assert().
const char * name
Name of the codec implementation.
common internal API header
enum AVPictureType pict_type
Picture type of the frame.
int width
picture width / height.
Libavcodec external API header.
int linesize[AV_NUM_DATA_POINTERS]
For video, size in bytes of each picture line.
main external API structure.
int ff_get_buffer(AVCodecContext *avctx, AVFrame *frame, int flags)
Get a buffer for a frame.
planar YUV 4:1:0, 9bpp, (1 Cr & Cb sample per 4x4 Y samples)
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
common internal api header.
static int vcr1_decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *avpkt)
int key_frame
1 -> keyframe, 0-> not
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
static double cr(void *priv, double x, double y)
This structure stores compressed data.
#define AV_CODEC_CAP_DR1
Codec uses get_buffer() for allocating buffers and supports custom allocators.