FFmpeg: libavcodec/v408dec.c Source File

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libavcodec

v408dec.c

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1 /*

2 * v408 decoder

4 *

5 * This file is part of FFmpeg.

6 *

7 * FFmpeg is free software; you can redistribute it and/or

8 * modify it under the terms of the GNU Lesser General Public

9 * License as published by the Free Software Foundation; either

10 * version 2.1 of the License, or (at your option) any later version.

11 *

12 * FFmpeg is distributed in the hope that it will be useful,

13 * but WITHOUT ANY WARRANTY; without even the implied warranty of

14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU

15 * Lesser General Public License for more details.

16 *

17 * You should have received a copy of the GNU Lesser General Public

18 * License along with FFmpeg; if not, write to the Free Software

19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA

20 */

22 #include "avcodec.h"

23 #include "codec_internal.h"

24 #include "decode.h"

26 static av_cold int v408_decode_init(AVCodecContext *avctx)

27 {

28 avctx->pix_fmt = AV_PIX_FMT_YUVA444P;

30 av_log(avctx, AV_LOG_WARNING, "This decoder is deprecated and will be removed.\n");

32 return 0;

33 }

35 static int v408_decode_frame(AVCodecContext *avctx, AVFrame *pic,

36 int *got_frame, AVPacket *avpkt)

37 {

38 const uint8_t *src = avpkt->data;

39 uint8_t *y, *u, *v, *a;

40 int i, j, ret;

42 if (avpkt->size < 4 * avctx->height * avctx->width) {

43 av_log(avctx, AV_LOG_ERROR, "Insufficient input data.\n");

44 return AVERROR(EINVAL);

45 }

47 if ((ret = ff_get_buffer(avctx, pic, 0)) < 0)

48 return ret;

50 y = pic->data[0];

51 u = pic->data[1];

52 v = pic->data[2];

53 a = pic->data[3];

55 for (i = 0; i < avctx->height; i++) {

56 for (j = 0; j < avctx->width; j++) {

57 u[j] = *src++;

58 y[j] = *src++;

59 v[j] = *src++;

60 a[j] = *src++;

61 }

63 y += pic->linesize[0];

64 u += pic->linesize[1];

65 v += pic->linesize[2];

66 a += pic->linesize[3];

67 }

69 *got_frame = 1;

71 return avpkt->size;

72 }

74 const FFCodec ff_v408_decoder = {

75 .p.name = "v408",

76 CODEC_LONG_NAME("Uncompressed packed QT 4:4:4:4"),

77 .p.type = AVMEDIA_TYPE_VIDEO,

78 .p.id = AV_CODEC_ID_V408,

79 .init = v408_decode_init,

80 FF_CODEC_DECODE_CB(v408_decode_frame),

81 .p.capabilities = AV_CODEC_CAP_DR1,

82 };

AV_LOG_WARNING

#define AV_LOG_WARNING

Something somehow does not look correct.

Definition: log.h:216

AVERROR

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

AVFrame

This structure describes decoded (raw) audio or video data.

Definition: frame.h:427

#define u(width, name, range_min, range_max)

Definition: cbs_apv.c:68

AVPacket::data

uint8_t * data

Definition: packet.h:558

FFCodec

Definition: codec_internal.h:127

AVFrame::data

uint8_t * data[AV_NUM_DATA_POINTERS]

pointer to the picture/channel planes.

Definition: frame.h:448

FFCodec::p

AVCodec p

The public AVCodec.

Definition: codec_internal.h:131

AV_LOG_ERROR

#define AV_LOG_ERROR

Something went wrong and cannot losslessly be recovered.

Definition: log.h:210

av_cold

#define av_cold

Definition: attributes.h:106

FF_CODEC_DECODE_CB

#define FF_CODEC_DECODE_CB(func)

Definition: codec_internal.h:346

decode.h

CODEC_LONG_NAME

#define CODEC_LONG_NAME(str)

Definition: codec_internal.h:331

ff_get_buffer

int ff_get_buffer(AVCodecContext *avctx, AVFrame *frame, int flags)

Get a buffer for a frame.

Definition: decode.c:1720

AV_CODEC_CAP_DR1

#define AV_CODEC_CAP_DR1

Codec uses get_buffer() or get_encode_buffer() for allocating buffers and supports custom allocators.

Definition: codec.h:52

AVPacket::size

int size

Definition: packet.h:559

codec_internal.h

v408_decode_frame

static int v408_decode_frame(AVCodecContext *avctx, AVFrame *pic, int *got_frame, AVPacket *avpkt)

Definition: v408dec.c:35

AV_CODEC_ID_V408

@ AV_CODEC_ID_V408

Definition: codec_id.h:261

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

Definition: undefined.txt:41

AV_PIX_FMT_YUVA444P

@ AV_PIX_FMT_YUVA444P

planar YUV 4:4:4 32bpp, (1 Cr & Cb sample per 1x1 Y & A samples)

Definition: pixfmt.h:174

#define i(width, name, range_min, range_max)

Definition: cbs_h2645.c:256

AVCodec::name

const char * name

Name of the codec implementation.

Definition: codec.h:179

AVCodecContext::height