[FFmpeg-devel] [PATCH] gifdec: port to bytestream2 API
Paul B Mahol
onemda at gmail.com
Wed Dec 5 17:42:13 CET 2012
While here remove ff_lzw_cur_ptr() as it become obsolete.
Signed-off-by: Paul B Mahol <onemda at gmail.com>
---
libavcodec/gifdec.c | 98 +++++++++++++++++++++++++----------------------------
libavcodec/lzw.c | 5 ---
libavcodec/lzw.h | 1 -
3 files changed, 46 insertions(+), 58 deletions(-)
diff --git a/libavcodec/gifdec.c b/libavcodec/gifdec.c
index acd9b29..5a1d248 100644
--- a/libavcodec/gifdec.c
+++ b/libavcodec/gifdec.c
@@ -65,9 +65,8 @@ typedef struct GifState {
int stored_img_size;
int stored_bg_color;
+ GetByteContext gb;
/* LZW compatible decoder */
- const uint8_t *bytestream;
- const uint8_t *bytestream_end;
LZWState *lzw;
/* aux buffers */
@@ -79,12 +78,12 @@ typedef struct GifState {
int trans_color; /**< color value that is used instead of transparent color */
} GifState;
-static void gif_read_palette(const uint8_t **buf, uint32_t *pal, int nb)
+static void gif_read_palette(GifState *s, uint32_t *pal, int nb)
{
- const uint8_t *pal_end = *buf + nb * 3;
+ int i;
- for (; *buf < pal_end; *buf += 3, pal++)
- *pal = (0xffu << 24) | AV_RB24(*buf);
+ for (i = 0; i < nb; i++, pal++)
+ *pal = (0xffu << 24) | bytestream2_get_be24u(&s->gb);
}
static void gif_fill(AVFrame *picture, uint32_t color)
@@ -141,14 +140,14 @@ static int gif_read_image(GifState *s)
uint8_t *idx;
/* At least 9 bytes of Image Descriptor. */
- if (s->bytestream_end < s->bytestream + 9)
+ if (bytestream2_get_bytes_left(&s->gb) < 9)
return AVERROR_INVALIDDATA;
- left = bytestream_get_le16(&s->bytestream);
- top = bytestream_get_le16(&s->bytestream);
- width = bytestream_get_le16(&s->bytestream);
- height = bytestream_get_le16(&s->bytestream);
- flags = bytestream_get_byte(&s->bytestream);
+ left = bytestream2_get_le16u(&s->gb);
+ top = bytestream2_get_le16u(&s->gb);
+ width = bytestream2_get_le16u(&s->gb);
+ height = bytestream2_get_le16u(&s->gb);
+ flags = bytestream2_get_byteu(&s->gb);
is_interleaved = flags & 0x40;
has_local_palette = flags & 0x80;
bits_per_pixel = (flags & 0x07) + 1;
@@ -158,10 +157,10 @@ static int gif_read_image(GifState *s)
if (has_local_palette) {
pal_size = 1 << bits_per_pixel;
- if (s->bytestream_end < s->bytestream + pal_size * 3)
+ if (bytestream2_get_bytes_left(&s->gb) < pal_size * 3)
return AVERROR_INVALIDDATA;
- gif_read_palette(&s->bytestream, s->local_palette, pal_size);
+ gif_read_palette(s, s->local_palette, pal_size);
pal = s->local_palette;
} else {
if (!s->has_global_palette) {
@@ -218,13 +217,13 @@ static int gif_read_image(GifState *s)
}
/* Expect at least 2 bytes: 1 for lzw code size and 1 for block size. */
- if (s->bytestream_end < s->bytestream + 2)
+ if (bytestream2_get_bytes_left(&s->gb) < 2)
return AVERROR_INVALIDDATA;
/* now get the image data */
- code_size = bytestream_get_byte(&s->bytestream);
- if ((ret = ff_lzw_decode_init(s->lzw, code_size, s->bytestream,
- s->bytestream_end - s->bytestream, FF_LZW_GIF)) < 0) {
+ code_size = bytestream2_get_byteu(&s->gb);
+ if ((ret = ff_lzw_decode_init(s->lzw, code_size, s->gb.buffer,
+ bytestream2_get_bytes_left(&s->gb), FF_LZW_GIF)) < 0) {
av_log(s->avctx, AV_LOG_ERROR, "LZW init failed\n");
return ret;
}
@@ -281,7 +280,6 @@ static int gif_read_image(GifState *s)
decode_tail:
/* read the garbage data until end marker is found */
ff_lzw_decode_tail(s->lzw);
- s->bytestream = ff_lzw_cur_ptr(s->lzw);
/* Graphic Control Extension's scope is single frame.
* Remove its influence. */
@@ -293,15 +291,15 @@ static int gif_read_image(GifState *s)
static int gif_read_extension(GifState *s)
{
- int ext_code, ext_len, i, gce_flags, gce_transparent_index;
+ int ext_code, ext_len, gce_flags, gce_transparent_index;
/* There must be at least 2 bytes:
* 1 for extension label and 1 for extension length. */
- if (s->bytestream_end < s->bytestream + 2)
+ if (bytestream2_get_bytes_left(&s->gb) < 2)
return AVERROR_INVALIDDATA;
- ext_code = bytestream_get_byte(&s->bytestream);
- ext_len = bytestream_get_byte(&s->bytestream);
+ ext_code = bytestream2_get_byteu(&s->gb);
+ ext_len = bytestream2_get_byteu(&s->gb);
av_dlog(s->avctx, "ext_code=0x%x len=%d\n", ext_code, ext_len);
@@ -312,13 +310,13 @@ static int gif_read_extension(GifState *s)
/* We need at least 5 bytes more: 4 is for extension body
* and 1 for next block size. */
- if (s->bytestream_end < s->bytestream + 5)
+ if (bytestream2_get_bytes_left(&s->gb) < 5)
return AVERROR_INVALIDDATA;
s->transparent_color_index = -1;
- gce_flags = bytestream_get_byte(&s->bytestream);
- bytestream_get_le16(&s->bytestream); // delay during which the frame is shown
- gce_transparent_index = bytestream_get_byte(&s->bytestream);
+ gce_flags = bytestream2_get_byteu(&s->gb);
+ bytestream2_skipu(&s->gb, 2); // delay during which the frame is shown
+ gce_transparent_index = bytestream2_get_byteu(&s->gb);
if (gce_flags & 0x01)
s->transparent_color_index = gce_transparent_index;
else
@@ -334,7 +332,7 @@ static int gif_read_extension(GifState *s)
av_dlog(s->avctx, "invalid value in gce_disposal (%d). Using default value of 0.\n", ext_len);
}
- ext_len = bytestream_get_byte(&s->bytestream);
+ ext_len = bytestream2_get_byteu(&s->gb);
break;
}
@@ -342,12 +340,11 @@ static int gif_read_extension(GifState *s)
discard_ext:
while (ext_len != 0) {
/* There must be at least ext_len bytes and 1 for next block size byte. */
- if (s->bytestream_end < s->bytestream + ext_len + 1)
+ if (bytestream2_get_bytes_left(&s->gb) < ext_len + 1)
return AVERROR_INVALIDDATA;
- for (i = 0; i < ext_len; i++)
- bytestream_get_byte(&s->bytestream);
- ext_len = bytestream_get_byte(&s->bytestream);
+ bytestream2_skipu(&s->gb, ext_len);
+ ext_len = bytestream2_get_byteu(&s->gb);
av_dlog(s->avctx, "ext_len1=%d\n", ext_len);
}
@@ -360,19 +357,19 @@ static int gif_read_header1(GifState *s)
int v, n;
int background_color_index;
- if (s->bytestream_end < s->bytestream + 13)
+ if (bytestream2_get_bytes_left(&s->gb) < 13)
return AVERROR_INVALIDDATA;
/* read gif signature */
- bytestream_get_buffer(&s->bytestream, sig, 6);
+ bytestream2_get_bufferu(&s->gb, sig, 6);
if (memcmp(sig, gif87a_sig, 6) != 0 &&
memcmp(sig, gif89a_sig, 6) != 0)
return AVERROR_INVALIDDATA;
/* read screen header */
s->transparent_color_index = -1;
- s->screen_width = bytestream_get_le16(&s->bytestream);
- s->screen_height = bytestream_get_le16(&s->bytestream);
+ s->screen_width = bytestream2_get_le16u(&s->gb);
+ s->screen_height = bytestream2_get_le16u(&s->gb);
if( (unsigned)s->screen_width > 32767
|| (unsigned)s->screen_height > 32767){
av_log(s->avctx, AV_LOG_ERROR, "picture size too large\n");
@@ -383,12 +380,12 @@ static int gif_read_header1(GifState *s)
if (!s->idx_line)
return AVERROR(ENOMEM);
- v = bytestream_get_byte(&s->bytestream);
+ v = bytestream2_get_byteu(&s->gb);
s->color_resolution = ((v & 0x70) >> 4) + 1;
s->has_global_palette = (v & 0x80);
s->bits_per_pixel = (v & 0x07) + 1;
- background_color_index = bytestream_get_byte(&s->bytestream);
- n = bytestream_get_byte(&s->bytestream);
+ background_color_index = bytestream2_get_byteu(&s->gb);
+ n = bytestream2_get_byteu(&s->gb);
if (n) {
s->avctx->sample_aspect_ratio.num = n + 15;
s->avctx->sample_aspect_ratio.den = 64;
@@ -401,10 +398,10 @@ static int gif_read_header1(GifState *s)
if (s->has_global_palette) {
s->background_color_index = background_color_index;
n = 1 << s->bits_per_pixel;
- if (s->bytestream_end < s->bytestream + n * 3)
+ if (bytestream2_get_bytes_left(&s->gb) < n * 3)
return AVERROR_INVALIDDATA;
- gif_read_palette(&s->bytestream, s->global_palette, n);
+ gif_read_palette(s, s->global_palette, n);
s->bg_color = s->global_palette[s->background_color_index];
} else
s->background_color_index = -1;
@@ -416,8 +413,8 @@ static int gif_parse_next_image(GifState *s, int *got_picture)
{
int ret;
*got_picture = sizeof(AVPicture);
- while (s->bytestream < s->bytestream_end) {
- int code = bytestream_get_byte(&s->bytestream);
+ while (bytestream2_get_bytes_left(&s->gb)) {
+ int code = bytestream2_get_byte(&s->gb);
av_dlog(s->avctx, "code=%02x '%c'\n", code, code);
@@ -456,23 +453,20 @@ static av_cold int gif_decode_init(AVCodecContext *avctx)
static int gif_decode_frame(AVCodecContext *avctx, void *data, int *got_picture, AVPacket *avpkt)
{
- const uint8_t *buf = avpkt->data;
- int buf_size = avpkt->size;
GifState *s = avctx->priv_data;
AVFrame *picture = data;
int ret;
+ bytestream2_init(&s->gb, avpkt->data, avpkt->size);
+
s->picture.pts = avpkt->pts;
s->picture.pkt_pts = avpkt->pts;
s->picture.pkt_dts = avpkt->dts;
s->picture.pkt_duration = avpkt->duration;
- s->bytestream = buf;
- s->bytestream_end = buf + buf_size;
-
- if (buf_size >= 6) {
- s->keyframe = memcmp(s->bytestream, gif87a_sig, 6) == 0 ||
- memcmp(s->bytestream, gif89a_sig, 6) == 0;
+ if (avpkt->size >= 6) {
+ s->keyframe = memcmp(avpkt->data, gif87a_sig, 6) == 0 ||
+ memcmp(avpkt->data, gif89a_sig, 6) == 0;
} else {
s->keyframe = 0;
}
@@ -511,7 +505,7 @@ static int gif_decode_frame(AVCodecContext *avctx, void *data, int *got_picture,
else if (*got_picture)
*picture = s->picture;
- return s->bytestream - buf;
+ return avpkt->size;
}
static av_cold int gif_decode_close(AVCodecContext *avctx)
diff --git a/libavcodec/lzw.c b/libavcodec/lzw.c
index 97f6e6a..43e3e05 100644
--- a/libavcodec/lzw.c
+++ b/libavcodec/lzw.c
@@ -92,11 +92,6 @@ static int lzw_get_code(struct LZWState * s)
return c & s->curmask;
}
-const uint8_t* ff_lzw_cur_ptr(LZWState *p)
-{
- return ((struct LZWState*)p)->pbuf;
-}
-
void ff_lzw_decode_tail(LZWState *p)
{
struct LZWState *s = (struct LZWState *)p;
diff --git a/libavcodec/lzw.h b/libavcodec/lzw.h
index 115ca4e..4653c1c 100644
--- a/libavcodec/lzw.h
+++ b/libavcodec/lzw.h
@@ -47,7 +47,6 @@ void ff_lzw_decode_open(LZWState **p);
void ff_lzw_decode_close(LZWState **p);
int ff_lzw_decode_init(LZWState *s, int csize, const uint8_t *buf, int buf_size, int mode);
int ff_lzw_decode(LZWState *s, uint8_t *buf, int len);
-const uint8_t* ff_lzw_cur_ptr(LZWState *lzw);
void ff_lzw_decode_tail(LZWState *lzw);
/** LZW encode state */
--
1.7.11.4
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