2 * DPX (.dpx) image decoder
3 * Copyright (c) 2009 Jimmy Christensen
5 * This file is part of FFmpeg.
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.
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.
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
22 #include "libavutil/intreadwrite.h"
23 #include "libavutil/imgutils.h"
24 #include "bytestream.h"
27 typedef struct DPXContext {
32 static unsigned int read32(const uint8_t **ptr, int is_big)
44 static inline unsigned make_16bit(unsigned value)
46 // mask away invalid bits
48 // correctly expand to 16 bits
49 return value + (value >> 10);
52 static int decode_frame(AVCodecContext *avctx,
57 const uint8_t *buf = avpkt->data;
58 const uint8_t *buf_end = avpkt->data + avpkt->size;
59 int buf_size = avpkt->size;
60 DPXContext *const s = avctx->priv_data;
61 AVFrame *picture = data;
62 AVFrame *const p = &s->picture;
65 int magic_num, offset, endian;
67 int w, h, stride, bits_per_color, descriptor, elements, target_packet_size, source_packet_size;
69 unsigned int rgbBuffer;
71 magic_num = AV_RB32(buf);
74 /* Check if the files "magic number" is "SDPX" which means it uses
75 * big-endian or XPDS which is for little-endian files */
76 if (magic_num == AV_RL32("SDPX")) {
78 } else if (magic_num == AV_RB32("SDPX")) {
81 av_log(avctx, AV_LOG_ERROR, "DPX marker not found\n");
85 offset = read32(&buf, endian);
86 // Need to end in 0x304 offset from start of file
87 buf = avpkt->data + 0x304;
88 w = read32(&buf, endian);
89 h = read32(&buf, endian);
91 // Need to end in 0x320 to read the descriptor
95 // Need to end in 0x323 to read the bits per color
97 avctx->bits_per_raw_sample =
98 bits_per_color = buf[0];
100 switch (descriptor) {
108 av_log(avctx, AV_LOG_ERROR, "Unsupported descriptor %d\n", descriptor);
112 switch (bits_per_color) {
115 avctx->pix_fmt = PIX_FMT_RGBA;
117 avctx->pix_fmt = PIX_FMT_RGB24;
119 source_packet_size = elements;
120 target_packet_size = elements;
123 avctx->pix_fmt = PIX_FMT_RGB48;
124 target_packet_size = 6;
125 source_packet_size = elements * 2;
130 avctx->pix_fmt = PIX_FMT_RGB48BE;
132 avctx->pix_fmt = PIX_FMT_RGB48LE;
134 target_packet_size = 6;
135 source_packet_size = elements * 2;
138 av_log(avctx, AV_LOG_ERROR, "Unsupported color depth : %d\n", bits_per_color);
142 if (s->picture.data[0])
143 avctx->release_buffer(avctx, &s->picture);
144 if (av_image_check_size(w, h, 0, avctx))
146 if (w != avctx->width || h != avctx->height)
147 avcodec_set_dimensions(avctx, w, h);
148 if (avctx->get_buffer(avctx, p) < 0) {
149 av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
153 // Move pointer to offset from start of file
154 buf = avpkt->data + offset;
157 stride = p->linesize[0];
159 switch (bits_per_color) {
161 for (x = 0; x < avctx->height; x++) {
162 uint16_t *dst = (uint16_t*)ptr;
163 for (y = 0; y < avctx->width; y++) {
164 rgbBuffer = read32(&buf, endian);
165 // Read out the 10-bit colors and convert to 16-bit
166 *dst++ = make_16bit(rgbBuffer >> 16);
167 *dst++ = make_16bit(rgbBuffer >> 6);
168 *dst++ = make_16bit(rgbBuffer << 4);
174 case 12: // Treat 12-bit as 16-bit
176 if (source_packet_size*avctx->width*avctx->height > buf_end - buf) {
177 av_log(avctx, AV_LOG_ERROR, "Overread buffer. Invalid header?\n");
180 if (source_packet_size == target_packet_size) {
181 for (x = 0; x < avctx->height; x++) {
182 memcpy(ptr, buf, target_packet_size*avctx->width);
184 buf += source_packet_size*avctx->width;
187 for (x = 0; x < avctx->height; x++) {
189 for (y = 0; y < avctx->width; y++) {
190 memcpy(dst, buf, target_packet_size);
191 dst += target_packet_size;
192 buf += source_packet_size;
200 *picture = s->picture;
201 *data_size = sizeof(AVPicture);
206 static av_cold int decode_init(AVCodecContext *avctx)
208 DPXContext *s = avctx->priv_data;
209 avcodec_get_frame_defaults(&s->picture);
210 avctx->coded_frame = &s->picture;
214 static av_cold int decode_end(AVCodecContext *avctx)
216 DPXContext *s = avctx->priv_data;
217 if (s->picture.data[0])
218 avctx->release_buffer(avctx, &s->picture);
223 AVCodec ff_dpx_decoder = {
234 .long_name = NULL_IF_CONFIG_SMALL("DPX image"),