FFmpeg: libavcodec/bitpacked_dec.c Source File

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libavcodec

bitpacked_dec.c

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1 /*

2 * Unpack bit-packed streams to formats supported by FFmpeg

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 /* Development sponsored by CBC/Radio-Canada */

24 /**

25 * @file

26 * Bitpacked

27 */

29 #include "avcodec.h"

30 #include "codec_internal.h"

31 #include "libavutil/imgutils.h"

32 #include "thread.h"

34 struct BitpackedContext {

35 int (*decode)(AVCodecContext *avctx, AVFrame *frame,

36 const AVPacket *pkt);

37 };

39 /* For this format, it's a simple passthrough */

40 static int bitpacked_decode_uyvy422(AVCodecContext *avctx, AVFrame *frame,

41 const AVPacket *avpkt)

42 {

43 int ret;

45 /* there is no need to copy as the data already match

46 * a known pixel format */

47 frame->buf[0] = av_buffer_ref(avpkt->buf);

48 if (!frame->buf[0]) {

49 return AVERROR(ENOMEM);

50 }

52 ret = av_image_fill_arrays(frame->data, frame->linesize, avpkt->data,

53 avctx->pix_fmt, avctx->width, avctx->height, 1);

54 if (ret < 0) {

55 av_buffer_unref(&frame->buf[0]);

56 return ret;

57 }

59 return 0;

60 }

62 static int bitpacked_decode_yuv422p10(AVCodecContext *avctx, AVFrame *frame,

63 const AVPacket *avpkt)

64 {

65 uint64_t frame_size = (uint64_t)avctx->width * (uint64_t)avctx->height * 20;

66 uint64_t packet_size = (uint64_t)avpkt->size * 8;

67 uint8_t *src;

68 uint16_t *y, *u, *v;

69 int ret, i, j;

71 ret = ff_thread_get_buffer(avctx, frame, 0);

72 if (ret < 0)

73 return ret;

75 if (frame_size > packet_size)

76 return AVERROR_INVALIDDATA;

78 if (avctx->width % 2)

79 return AVERROR_PATCHWELCOME;

81 src = avpkt->data;

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

83 y = (uint16_t*)(frame->data[0] + i * frame->linesize[0]);

84 u = (uint16_t*)(frame->data[1] + i * frame->linesize[1]);

85 v = (uint16_t*)(frame->data[2] + i * frame->linesize[2]);

87 for (j = 0; j < avctx->width; j += 2) {

88 *u++ = (src[0] << 2) | (src[1] >> 6);

89 *v++ = ((src[2] << 6) | (src[3] >> 2)) & 0x3ff;

90 *y++ = ((src[1] << 4) | (src[2] >> 4)) & 0x3ff;

91 *y++ = ((src[3] << 8) | (src[4])) & 0x3ff;

92 src += 5;

93 }

94 }

96 return 0;

97 }

99 static av_cold int bitpacked_init_decoder(AVCodecContext *avctx)

100 {

101 struct BitpackedContext *bc = avctx->priv_data;

102

103 if (!avctx->codec_tag || !avctx->width || !avctx->height)

104 return AVERROR_INVALIDDATA;

105

106 if (avctx->codec_tag == MKTAG('U', 'Y', 'V', 'Y')) {

107 if (avctx->bits_per_coded_sample == 16 &&

108 avctx->pix_fmt == AV_PIX_FMT_UYVY422)

109 bc->decode = bitpacked_decode_uyvy422;

110 else if (avctx->bits_per_coded_sample == 20 &&

111 avctx->pix_fmt == AV_PIX_FMT_YUV422P10)

112 bc->decode = bitpacked_decode_yuv422p10;

113 else

114 return AVERROR_INVALIDDATA;

115 } else {

116 return AVERROR_INVALIDDATA;

117 }

118

119 return 0;

120 }

121

122 static int bitpacked_decode(AVCodecContext *avctx, AVFrame *frame,

123 int *got_frame, AVPacket *avpkt)

124 {

125 struct BitpackedContext *bc = avctx->priv_data;

126 int buf_size = avpkt->size;

127 int res;

128

129 res = bc->decode(avctx, frame, avpkt);

130 if (res)

131 return res;

132

133 *got_frame = 1;

134 return buf_size;

135

136 }

137

138 const FFCodec ff_bitpacked_decoder = {

139 .p.name = "bitpacked",

140 CODEC_LONG_NAME("Bitpacked"),

141 .p.type = AVMEDIA_TYPE_VIDEO,

142 .p.id = AV_CODEC_ID_BITPACKED,

143 .p.capabilities = AV_CODEC_CAP_FRAME_THREADS,

144 .priv_data_size = sizeof(struct BitpackedContext),

145 .init = bitpacked_init_decoder,

146 FF_CODEC_DECODE_CB(bitpacked_decode),

147 .codec_tags = (const uint32_t []){

148 MKTAG('U', 'Y', 'V', 'Y'),

149 FF_CODEC_TAGS_END,

150 },

151 };

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

bitpacked_decode

static int bitpacked_decode(AVCodecContext *avctx, AVFrame *frame, int *got_frame, AVPacket *avpkt)

Definition: bitpacked_dec.c:122

AVPacket::data

uint8_t * data

Definition: packet.h:588

FFCodec

Definition: codec_internal.h:127

av_buffer_ref

AVBufferRef * av_buffer_ref(const AVBufferRef *buf)

Create a new reference to an AVBuffer.

Definition: buffer.c:103

thread.h

FFCodec::p

AVCodec p

The public AVCodec.

Definition: codec_internal.h:131

FF_CODEC_TAGS_END

#define FF_CODEC_TAGS_END

FFCodec.codec_tags termination value.

Definition: codec_internal.h:94

pkt

AVPacket * pkt

Definition: movenc.c:60

av_cold

#define av_cold

Definition: attributes.h:106

FF_CODEC_DECODE_CB

#define FF_CODEC_DECODE_CB(func)

Definition: codec_internal.h:347

frame_size

int frame_size

Definition: mxfenc.c:2487

ff_thread_get_buffer

int ff_thread_get_buffer(AVCodecContext *avctx, AVFrame *f, int flags)

Wrapper around get_buffer() for frame-multithreaded codecs.

Definition: pthread_frame.c:1038

bitpacked_init_decoder

static av_cold int bitpacked_init_decoder(AVCodecContext *avctx)

Definition: bitpacked_dec.c:99

CODEC_LONG_NAME

#define CODEC_LONG_NAME(str)

Definition: codec_internal.h:332

AV_CODEC_CAP_FRAME_THREADS

#define AV_CODEC_CAP_FRAME_THREADS

Codec supports frame-level multithreading.

Definition: codec.h:95

bitpacked_decode_yuv422p10

static int bitpacked_decode_yuv422p10(AVCodecContext *avctx, AVFrame *frame, const AVPacket *avpkt)

Definition: bitpacked_dec.c:62

AVPacket::buf

AVBufferRef * buf

A reference to the reference-counted buffer where the packet data is stored.

Definition: packet.h:571

ff_bitpacked_decoder

const FFCodec ff_bitpacked_decoder

Definition: bitpacked_dec.c:138

AVERROR_PATCHWELCOME

#define AVERROR_PATCHWELCOME

Not yet implemented in FFmpeg, patches welcome.

Definition: error.h:64

av_buffer_unref

void av_buffer_unref(AVBufferRef **buf)

Free a given reference and automatically free the buffer if there are no more references to it.

Definition: buffer.c:139

AV_PIX_FMT_YUV422P10

#define AV_PIX_FMT_YUV422P10

Definition: pixfmt.h:540

BitpackedContext

Definition: bitpacked_dec.c:34

init

int(* init)(AVBSFContext *ctx)

Definition: dts2pts.c:550

AVPacket::size

int size

Definition: packet.h:589

av_image_fill_arrays

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.

Definition: imgutils.c:446

codec_internal.h

AV_CODEC_ID_BITPACKED

@ AV_CODEC_ID_BITPACKED

Definition: codec_id.h:285

AVCodecContext::bits_per_coded_sample

int bits_per_coded_sample

bits per sample/pixel from the demuxer (needed for huffyuv).

Definition: avcodec.h:1546

#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

int height

Definition: avcodec.h:592

AVCodecContext::pix_fmt

enum AVPixelFormat pix_fmt

Pixel format, see AV_PIX_FMT_xxx.

Definition: avcodec.h:631

avcodec.h

ret

Definition: filter_design.txt:187

frame

these buffered frames must be flushed immediately if a new input produces new the filter must not call request_frame to get more It must just process the frame or queue it The task of requesting more frames is left to the filter s request_frame method or the application If a filter has several the filter must be ready for frames arriving randomly on any input any filter with several inputs will most likely require some kind of queuing mechanism It is perfectly acceptable to have a limited queue and to drop frames when the inputs are too unbalanced request_frame For filters that do not use the this method is called when a frame is wanted on an output For a it should directly call filter_frame on the corresponding output For a if there are queued frames already one of these frames should be pushed If the filter should request a frame on one of its repeatedly until at least one frame has been pushed Return or at least make progress towards producing a frame

Definition: filter_design.txt:265

bitpacked_decode_uyvy422

static int bitpacked_decode_uyvy422(AVCodecContext *avctx, AVFrame *frame, const AVPacket *avpkt)

Definition: bitpacked_dec.c:40

AV_PIX_FMT_UYVY422

@ AV_PIX_FMT_UYVY422

packed YUV 4:2:2, 16bpp, Cb Y0 Cr Y1

Definition: pixfmt.h:88

AVCodecContext

main external API structure.

Definition: avcodec.h:431

AVMEDIA_TYPE_VIDEO