1
0
mirror of https://github.com/FFmpeg/FFmpeg.git synced 2024-11-26 19:01:44 +02:00

avcodec/sgidec: Avoid redundant private context

SGI is intra-frame only; the decoder therefore does not
maintain any state between frames, so remove
the private context.

Also rename depth to nb_components.

Reviewed-by: Tomas Härdin <git@haerdin.se>
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
This commit is contained in:
Andreas Rheinhardt 2022-09-29 16:05:49 +02:00
parent 54cf0482bd
commit e771223ec1

View File

@ -25,25 +25,17 @@
#include "decode.h"
#include "sgi.h"
typedef struct SgiState {
AVCodecContext *avctx;
unsigned int width;
int height;
unsigned int depth;
unsigned int bytes_per_channel;
int linesize;
GetByteContext g;
} SgiState;
/**
* Expand an RLE row into a channel.
* @param s the current image state
* @param logctx a logcontext
* @param out_buf Points to one line after the output buffer.
* @param g GetByteContext used to read input from
* @param len length of out_buf in bytes
* @param pixelstride pixel stride of input buffer
* @return size of output in bytes, else return error code.
*/
static int expand_rle_row8(SgiState *s, uint8_t *out_buf,
static int expand_rle_row8(void *logctx, uint8_t *out_buf,
GetByteContext *g,
int len, int pixelstride)
{
unsigned char pixel, count;
@ -51,26 +43,26 @@ static int expand_rle_row8(SgiState *s, uint8_t *out_buf,
uint8_t *out_end = out_buf + len;
while (out_buf < out_end) {
if (bytestream2_get_bytes_left(&s->g) < 1)
if (bytestream2_get_bytes_left(g) < 1)
return AVERROR_INVALIDDATA;
pixel = bytestream2_get_byteu(&s->g);
pixel = bytestream2_get_byteu(g);
if (!(count = (pixel & 0x7f))) {
break;
}
/* Check for buffer overflow. */
if (out_end - out_buf <= pixelstride * (count - 1)) {
av_log(s->avctx, AV_LOG_ERROR, "Invalid pixel count.\n");
av_log(logctx, AV_LOG_ERROR, "Invalid pixel count.\n");
return AVERROR_INVALIDDATA;
}
if (pixel & 0x80) {
while (count--) {
*out_buf = bytestream2_get_byte(&s->g);
*out_buf = bytestream2_get_byte(g);
out_buf += pixelstride;
}
} else {
pixel = bytestream2_get_byte(&s->g);
pixel = bytestream2_get_byte(g);
while (count--) {
*out_buf = pixel;
@ -81,7 +73,8 @@ static int expand_rle_row8(SgiState *s, uint8_t *out_buf,
return (out_buf - orig) / pixelstride;
}
static int expand_rle_row16(SgiState *s, uint16_t *out_buf,
static int expand_rle_row16(void *logctx, uint16_t *out_buf,
GetByteContext *g,
int len, int pixelstride)
{
unsigned short pixel;
@ -90,26 +83,26 @@ static int expand_rle_row16(SgiState *s, uint16_t *out_buf,
uint16_t *out_end = out_buf + len;
while (out_buf < out_end) {
if (bytestream2_get_bytes_left(&s->g) < 2)
if (bytestream2_get_bytes_left(g) < 2)
return AVERROR_INVALIDDATA;
pixel = bytestream2_get_be16u(&s->g);
pixel = bytestream2_get_be16u(g);
if (!(count = (pixel & 0x7f)))
break;
/* Check for buffer overflow. */
if (out_end - out_buf <= pixelstride * (count - 1)) {
av_log(s->avctx, AV_LOG_ERROR, "Invalid pixel count.\n");
av_log(logctx, AV_LOG_ERROR, "Invalid pixel count.\n");
return AVERROR_INVALIDDATA;
}
if (pixel & 0x80) {
while (count--) {
pixel = bytestream2_get_ne16(&s->g);
pixel = bytestream2_get_ne16(g);
AV_WN16A(out_buf, pixel);
out_buf += pixelstride;
}
} else {
pixel = bytestream2_get_ne16(&s->g);
pixel = bytestream2_get_ne16(g);
while (count--) {
AV_WN16A(out_buf, pixel);
@ -127,34 +120,38 @@ static int expand_rle_row16(SgiState *s, uint16_t *out_buf,
* @param s the current image state
* @return 0 if no error, else return error code.
*/
static int read_rle_sgi(uint8_t *last_line, SgiState *s)
static int read_rle_sgi(void *logctx, uint8_t *last_line, GetByteContext *g,
ptrdiff_t stride, unsigned width, unsigned height,
unsigned nb_components, unsigned bytes_per_channel)
{
uint8_t *dest_row;
unsigned int len = s->height * s->depth * 4;
GetByteContext g_table = s->g;
unsigned int len = height * nb_components * 4;
GetByteContext g_table = *g;
unsigned int start_offset;
int linesize, ret;
/* size of RLE offset and length tables */
if (len * 2 > bytestream2_get_bytes_left(&s->g)) {
if (len * 2 > bytestream2_get_bytes_left(g)) {
return AVERROR_INVALIDDATA;
}
for (unsigned z = 0; z < s->depth; z++) {
for (unsigned z = 0; z < nb_components; z++) {
dest_row = last_line;
for (int remaining_lines = s->height;;) {
linesize = s->width * s->depth;
for (unsigned remaining_lines = height;;) {
linesize = width * nb_components;
start_offset = bytestream2_get_be32(&g_table);
bytestream2_seek(&s->g, start_offset, SEEK_SET);
if (s->bytes_per_channel == 1)
ret = expand_rle_row8(s, dest_row + z, linesize, s->depth);
bytestream2_seek(g, start_offset, SEEK_SET);
if (bytes_per_channel == 1)
ret = expand_rle_row8(logctx, dest_row + z, g,
linesize, nb_components);
else
ret = expand_rle_row16(s, (uint16_t *)dest_row + z, linesize, s->depth);
if (ret != s->width)
ret = expand_rle_row16(logctx, (uint16_t *)dest_row + z, g,
linesize, nb_components);
if (ret != width)
return AVERROR_INVALIDDATA;
if (--remaining_lines == 0)
break;
dest_row -= s->linesize;
dest_row -= stride;
}
}
return 0;
@ -166,33 +163,34 @@ static int read_rle_sgi(uint8_t *last_line, SgiState *s)
* @param s the current image state
* @return 0 if read success, else return error code.
*/
static int read_uncompressed_sgi(unsigned char *out_buf, SgiState *s)
static int read_uncompressed_sgi(unsigned char *out_buf, GetByteContext *g,
ptrdiff_t stride, unsigned width, unsigned height,
unsigned nb_components, unsigned bytes_per_channel)
{
int x, y, z;
unsigned int offset = s->height * s->width * s->bytes_per_channel;
unsigned int offset = height * width * bytes_per_channel;
GetByteContext gp[4];
uint8_t *out_end;
/* Test buffer size. */
if (offset * s->depth > bytestream2_get_bytes_left(&s->g))
if (offset * nb_components > bytestream2_get_bytes_left(g))
return AVERROR_INVALIDDATA;
/* Create a reader for each plane */
for (z = 0; z < s->depth; z++) {
gp[z] = s->g;
for (unsigned z = 0; z < nb_components; z++) {
gp[z] = *g;
bytestream2_skip(&gp[z], z * offset);
}
for (y = s->height - 1; y >= 0; y--) {
out_end = out_buf + (y * s->linesize);
if (s->bytes_per_channel == 1) {
for (x = s->width; x > 0; x--)
for (z = 0; z < s->depth; z++)
for (int y = height - 1; y >= 0; y--) {
out_end = out_buf + y * stride;
if (bytes_per_channel == 1) {
for (unsigned x = width; x > 0; x--)
for (unsigned z = 0; z < nb_components; z++)
*out_end++ = bytestream2_get_byteu(&gp[z]);
} else {
uint16_t *out16 = (uint16_t *)out_end;
for (x = s->width; x > 0; x--)
for (z = 0; z < s->depth; z++)
for (unsigned x = width; x > 0; x--)
for (unsigned z = 0; z < nb_components; z++)
*out16++ = bytestream2_get_ne16u(&gp[z]);
}
}
@ -202,31 +200,32 @@ static int read_uncompressed_sgi(unsigned char *out_buf, SgiState *s)
static int decode_frame(AVCodecContext *avctx, AVFrame *p,
int *got_frame, AVPacket *avpkt)
{
SgiState *s = avctx->priv_data;
unsigned int dimension, rle;
GetByteContext g;
unsigned int bytes_per_channel, nb_components, dimension, rle, width;
int height;
int ret = 0;
uint8_t *out_buf, *last_line;
bytestream2_init(&s->g, avpkt->data, avpkt->size);
if (bytestream2_get_bytes_left(&s->g) < SGI_HEADER_SIZE) {
bytestream2_init(&g, avpkt->data, avpkt->size);
if (bytestream2_get_bytes_left(&g) < SGI_HEADER_SIZE) {
av_log(avctx, AV_LOG_ERROR, "buf_size too small (%d)\n", avpkt->size);
return AVERROR_INVALIDDATA;
}
/* Test for SGI magic. */
if (bytestream2_get_be16u(&s->g) != SGI_MAGIC) {
if (bytestream2_get_be16u(&g) != SGI_MAGIC) {
av_log(avctx, AV_LOG_ERROR, "bad magic number\n");
return AVERROR_INVALIDDATA;
}
rle = bytestream2_get_byteu(&s->g);
s->bytes_per_channel = bytestream2_get_byteu(&s->g);
dimension = bytestream2_get_be16u(&s->g);
s->width = bytestream2_get_be16u(&s->g);
s->height = bytestream2_get_be16u(&s->g);
s->depth = bytestream2_get_be16u(&s->g);
rle = bytestream2_get_byteu(&g);
bytes_per_channel = bytestream2_get_byteu(&g);
dimension = bytestream2_get_be16u(&g);
width = bytestream2_get_be16u(&g);
height = bytestream2_get_be16u(&g);
nb_components = bytestream2_get_be16u(&g);
if (s->bytes_per_channel != 1 && s->bytes_per_channel != 2) {
if (bytes_per_channel != 1 && bytes_per_channel != 2) {
av_log(avctx, AV_LOG_ERROR, "wrong channel number\n");
return AVERROR_INVALIDDATA;
}
@ -237,18 +236,18 @@ static int decode_frame(AVCodecContext *avctx, AVFrame *p,
return AVERROR_INVALIDDATA;
}
if (s->depth == SGI_GRAYSCALE) {
avctx->pix_fmt = s->bytes_per_channel == 2 ? AV_PIX_FMT_GRAY16BE : AV_PIX_FMT_GRAY8;
} else if (s->depth == SGI_RGB) {
avctx->pix_fmt = s->bytes_per_channel == 2 ? AV_PIX_FMT_RGB48BE : AV_PIX_FMT_RGB24;
} else if (s->depth == SGI_RGBA) {
avctx->pix_fmt = s->bytes_per_channel == 2 ? AV_PIX_FMT_RGBA64BE : AV_PIX_FMT_RGBA;
if (nb_components == SGI_GRAYSCALE) {
avctx->pix_fmt = bytes_per_channel == 2 ? AV_PIX_FMT_GRAY16BE : AV_PIX_FMT_GRAY8;
} else if (nb_components == SGI_RGB) {
avctx->pix_fmt = bytes_per_channel == 2 ? AV_PIX_FMT_RGB48BE : AV_PIX_FMT_RGB24;
} else if (nb_components == SGI_RGBA) {
avctx->pix_fmt = bytes_per_channel == 2 ? AV_PIX_FMT_RGBA64BE : AV_PIX_FMT_RGBA;
} else {
av_log(avctx, AV_LOG_ERROR, "wrong picture format\n");
return AVERROR_INVALIDDATA;
}
ret = ff_set_dimensions(avctx, s->width, s->height);
ret = ff_set_dimensions(avctx, width, height);
if (ret < 0)
return ret;
@ -259,16 +258,16 @@ static int decode_frame(AVCodecContext *avctx, AVFrame *p,
p->key_frame = 1;
out_buf = p->data[0];
last_line = out_buf + p->linesize[0] * (s->height - 1);
s->linesize = p->linesize[0];
last_line = out_buf + p->linesize[0] * (height - 1);
/* Skip header. */
bytestream2_seek(&s->g, SGI_HEADER_SIZE, SEEK_SET);
bytestream2_seek(&g, SGI_HEADER_SIZE, SEEK_SET);
if (rle) {
ret = read_rle_sgi(last_line, s);
ret = read_rle_sgi(avctx, last_line, &g, p->linesize[0],
width, height, nb_components, bytes_per_channel);
} else {
ret = read_uncompressed_sgi(out_buf, s);
ret = read_uncompressed_sgi(out_buf, &g, p->linesize[0],
width, height, nb_components, bytes_per_channel);
}
if (ret)
return ret;
@ -277,22 +276,11 @@ static int decode_frame(AVCodecContext *avctx, AVFrame *p,
return avpkt->size;
}
static av_cold int sgi_decode_init(AVCodecContext *avctx)
{
SgiState *s = avctx->priv_data;
s->avctx = avctx;
return 0;
}
const FFCodec ff_sgi_decoder = {
.p.name = "sgi",
CODEC_LONG_NAME("SGI image"),
.p.type = AVMEDIA_TYPE_VIDEO,
.p.id = AV_CODEC_ID_SGI,
.priv_data_size = sizeof(SgiState),
FF_CODEC_DECODE_CB(decode_frame),
.init = sgi_decode_init,
.p.capabilities = AV_CODEC_CAP_DR1,
};