std/jpeg: prepare to decode progressive JPEGs
diff --git a/release/c/wuffs-unsupported-snapshot.c b/release/c/wuffs-unsupported-snapshot.c
index 0dc4fbd..e808ab0 100644
--- a/release/c/wuffs-unsupported-snapshot.c
+++ b/release/c/wuffs-unsupported-snapshot.c
@@ -8901,6 +8901,7 @@
} s_decode_sos[1];
struct {
uint32_t v_i;
+ uint64_t scratch;
} s_prepare_scan[1];
} private_data;
@@ -38316,6 +38317,10 @@
bool v_has_v24 = false;
bool v_has_v3 = false;
uint32_t v_upper_bound = 0;
+ uint64_t v_wh0 = 0;
+ uint64_t v_wh1 = 0;
+ uint64_t v_wh2 = 0;
+ uint64_t v_wh3 = 0;
const uint8_t* iop_a_src = NULL;
const uint8_t* io0_a_src WUFFS_BASE__POTENTIALLY_UNUSED = NULL;
@@ -38559,11 +38564,15 @@
self->private_impl.f_components_workbuf_heights[1] = wuffs_base__u32__min(v_upper_bound, (8 * self->private_impl.f_height_in_mcus * ((uint32_t)(self->private_impl.f_components_v[1]))));
self->private_impl.f_components_workbuf_heights[2] = wuffs_base__u32__min(v_upper_bound, (8 * self->private_impl.f_height_in_mcus * ((uint32_t)(self->private_impl.f_components_v[2]))));
self->private_impl.f_components_workbuf_heights[3] = wuffs_base__u32__min(v_upper_bound, (8 * self->private_impl.f_height_in_mcus * ((uint32_t)(self->private_impl.f_components_v[3]))));
+ v_wh0 = (((uint64_t)(self->private_impl.f_components_workbuf_widths[0])) * ((uint64_t)(self->private_impl.f_components_workbuf_heights[0])));
+ v_wh1 = (((uint64_t)(self->private_impl.f_components_workbuf_widths[1])) * ((uint64_t)(self->private_impl.f_components_workbuf_heights[1])));
+ v_wh2 = (((uint64_t)(self->private_impl.f_components_workbuf_widths[2])) * ((uint64_t)(self->private_impl.f_components_workbuf_heights[2])));
+ v_wh3 = (((uint64_t)(self->private_impl.f_components_workbuf_widths[3])) * ((uint64_t)(self->private_impl.f_components_workbuf_heights[3])));
self->private_impl.f_components_workbuf_offsets[0] = 0;
- self->private_impl.f_components_workbuf_offsets[1] = (self->private_impl.f_components_workbuf_offsets[0] + (((uint64_t)(self->private_impl.f_components_workbuf_widths[0])) * ((uint64_t)(self->private_impl.f_components_workbuf_heights[0]))));
- self->private_impl.f_components_workbuf_offsets[2] = (self->private_impl.f_components_workbuf_offsets[1] + (((uint64_t)(self->private_impl.f_components_workbuf_widths[1])) * ((uint64_t)(self->private_impl.f_components_workbuf_heights[1]))));
- self->private_impl.f_components_workbuf_offsets[3] = (self->private_impl.f_components_workbuf_offsets[2] + (((uint64_t)(self->private_impl.f_components_workbuf_widths[2])) * ((uint64_t)(self->private_impl.f_components_workbuf_heights[2]))));
- self->private_impl.f_components_workbuf_offsets[4] = (self->private_impl.f_components_workbuf_offsets[3] + (((uint64_t)(self->private_impl.f_components_workbuf_widths[3])) * ((uint64_t)(self->private_impl.f_components_workbuf_heights[3]))));
+ self->private_impl.f_components_workbuf_offsets[1] = (self->private_impl.f_components_workbuf_offsets[0] + v_wh0);
+ self->private_impl.f_components_workbuf_offsets[2] = (self->private_impl.f_components_workbuf_offsets[1] + v_wh1);
+ self->private_impl.f_components_workbuf_offsets[3] = (self->private_impl.f_components_workbuf_offsets[2] + v_wh2);
+ self->private_impl.f_components_workbuf_offsets[4] = (self->private_impl.f_components_workbuf_offsets[3] + v_wh3);
goto ok;
ok:
@@ -39614,55 +39623,92 @@
goto exit;
}
}
- if ( ! self->private_impl.f_seen_dht[(0 | self->private_impl.f_scan_comps_td[v_i])] || ! self->private_impl.f_seen_dht[(4 | self->private_impl.f_scan_comps_ta[v_i])]) {
+ v_i += 1;
+ }
+ if (self->private_impl.f_sof_marker < 194) {
+ self->private_data.s_prepare_scan[0].scratch = 3;
+ WUFFS_BASE__COROUTINE_SUSPENSION_POINT(4);
+ if (self->private_data.s_prepare_scan[0].scratch > ((uint64_t)(io2_a_src - iop_a_src))) {
+ self->private_data.s_prepare_scan[0].scratch -= ((uint64_t)(io2_a_src - iop_a_src));
+ iop_a_src = io2_a_src;
+ status = wuffs_base__make_status(wuffs_base__suspension__short_read);
+ goto suspend;
+ }
+ iop_a_src += self->private_data.s_prepare_scan[0].scratch;
+ self->private_impl.f_scan_ss = 0;
+ self->private_impl.f_scan_se = 63;
+ self->private_impl.f_scan_ah = 0;
+ self->private_impl.f_scan_al = 0;
+ } else {
+ {
+ WUFFS_BASE__COROUTINE_SUSPENSION_POINT(5);
+ if (WUFFS_BASE__UNLIKELY(iop_a_src == io2_a_src)) {
+ status = wuffs_base__make_status(wuffs_base__suspension__short_read);
+ goto suspend;
+ }
+ uint8_t t_3 = *iop_a_src++;
+ v_c = t_3;
+ }
+ if (v_c > 63) {
+ status = wuffs_base__make_status(wuffs_jpeg__error__bad_sos_marker);
+ goto exit;
+ }
+ self->private_impl.f_scan_ss = v_c;
+ {
+ WUFFS_BASE__COROUTINE_SUSPENSION_POINT(6);
+ if (WUFFS_BASE__UNLIKELY(iop_a_src == io2_a_src)) {
+ status = wuffs_base__make_status(wuffs_base__suspension__short_read);
+ goto suspend;
+ }
+ uint8_t t_4 = *iop_a_src++;
+ v_c = t_4;
+ }
+ if ((v_c > 63) || (v_c < self->private_impl.f_scan_ss)) {
+ status = wuffs_base__make_status(wuffs_jpeg__error__bad_sos_marker);
+ goto exit;
+ }
+ self->private_impl.f_scan_se = v_c;
+ {
+ WUFFS_BASE__COROUTINE_SUSPENSION_POINT(7);
+ if (WUFFS_BASE__UNLIKELY(iop_a_src == io2_a_src)) {
+ status = wuffs_base__make_status(wuffs_base__suspension__short_read);
+ goto suspend;
+ }
+ uint8_t t_5 = *iop_a_src++;
+ v_c = t_5;
+ }
+ if (((v_c >> 4) > 14) || ((v_c & 15) > 13)) {
+ status = wuffs_base__make_status(wuffs_jpeg__error__bad_sos_marker);
+ goto exit;
+ }
+ self->private_impl.f_scan_ah = (v_c >> 4);
+ self->private_impl.f_scan_al = (v_c & 15);
+ if (self->private_impl.f_scan_ah > 0) {
+ if ((self->private_impl.f_scan_ah - 1) != self->private_impl.f_scan_al) {
+ status = wuffs_base__make_status(wuffs_jpeg__error__bad_sos_marker);
+ goto exit;
+ }
+ }
+ if (self->private_impl.f_scan_ss == 0) {
+ if (self->private_impl.f_scan_se != 0) {
+ status = wuffs_base__make_status(wuffs_jpeg__error__bad_sos_marker);
+ goto exit;
+ }
+ } else {
+ if (self->private_impl.f_scan_num_components != 1) {
+ status = wuffs_base__make_status(wuffs_jpeg__error__bad_sos_marker);
+ goto exit;
+ }
+ }
+ }
+ v_i = 0;
+ while (v_i < self->private_impl.f_scan_num_components) {
+ if (((self->private_impl.f_scan_ss == 0) && ! self->private_impl.f_seen_dht[(0 | self->private_impl.f_scan_comps_td[v_i])]) || ((self->private_impl.f_scan_se != 0) && ! self->private_impl.f_seen_dht[(4 | self->private_impl.f_scan_comps_ta[v_i])])) {
status = wuffs_base__make_status(wuffs_jpeg__error__missing_huffman_table);
goto exit;
}
v_i += 1;
}
- {
- WUFFS_BASE__COROUTINE_SUSPENSION_POINT(4);
- if (WUFFS_BASE__UNLIKELY(iop_a_src == io2_a_src)) {
- status = wuffs_base__make_status(wuffs_base__suspension__short_read);
- goto suspend;
- }
- uint8_t t_3 = *iop_a_src++;
- v_c = t_3;
- }
- if (v_c > 63) {
- status = wuffs_base__make_status(wuffs_jpeg__error__bad_sos_marker);
- goto exit;
- }
- self->private_impl.f_scan_ss = v_c;
- {
- WUFFS_BASE__COROUTINE_SUSPENSION_POINT(5);
- if (WUFFS_BASE__UNLIKELY(iop_a_src == io2_a_src)) {
- status = wuffs_base__make_status(wuffs_base__suspension__short_read);
- goto suspend;
- }
- uint8_t t_4 = *iop_a_src++;
- v_c = t_4;
- }
- if ((v_c > 63) || (v_c < self->private_impl.f_scan_ss)) {
- status = wuffs_base__make_status(wuffs_jpeg__error__bad_sos_marker);
- goto exit;
- }
- self->private_impl.f_scan_se = v_c;
- {
- WUFFS_BASE__COROUTINE_SUSPENSION_POINT(6);
- if (WUFFS_BASE__UNLIKELY(iop_a_src == io2_a_src)) {
- status = wuffs_base__make_status(wuffs_base__suspension__short_read);
- goto suspend;
- }
- uint8_t t_5 = *iop_a_src++;
- v_c = t_5;
- }
- if (((v_c >> 4) > 13) || ((v_c & 15) > 13)) {
- status = wuffs_base__make_status(wuffs_jpeg__error__bad_sos_marker);
- goto exit;
- }
- self->private_impl.f_scan_ah = (v_c >> 4);
- self->private_impl.f_scan_al = (v_c & 15);
self->private_impl.f_scan_width_in_mcus = self->private_impl.f_width_in_mcus;
self->private_impl.f_scan_height_in_mcus = self->private_impl.f_height_in_mcus;
if (self->private_impl.f_scan_num_components == 1) {
diff --git a/std/jpeg/decode_jpeg.wuffs b/std/jpeg/decode_jpeg.wuffs
index c5b5953..d776ad4 100644
--- a/std/jpeg/decode_jpeg.wuffs
+++ b/std/jpeg/decode_jpeg.wuffs
@@ -91,9 +91,65 @@
scan_comps_td : array[4] base.u8[..= 3],
scan_comps_ta : array[4] base.u8[..= 3],
+ // Every JPEG has a single SOI (Start Of Image) marker. Hierarchical
+ // JPEG images can have multiple Frames but this decoder does not
+ // support those. We thus expect a single SOF (Start Of Frame) for the
+ // single SOI.
+ //
+ // Sequential JPEGs have a single SOS (Start Of Scan) for the SOF.
+ // Their (Ss, Se, Ah, Al) below are effectively (0, 63, 0, 0).
+ //
+ // Progressive JPEGs have muliple Scans, incrementally building the 64
+ // coefficients (1 DC coefficient and 63 AC coefficients) of each
+ // pre-IDCT block. There are two independent aspects of progression.
+ //
+ // Spectral selection (the Ss and Se parameters) is when a subset of a
+ // 64 coefficients are in the scan. For example, three scans could hold
+ // coefficient 0 (the DC coefficient), coefficients 1 ..= 5 and then
+ // coefficients 6 ..= 63, in zig-zag order.
+ //
+ // Successive approximation (the Ah and Al parameters) is when a subset
+ // of the spectral-selected coefficients' 8 bits are in the scan
+ // (assuming 8-bit and not 12-bit or 16-bit JPEGs). For example, three
+ // scans could hold the 6 most significant bits, the second-least
+ // significant bit and then the least significant bit. A zero Ah value
+ // is a special case, meaning the scan holds (8 - Al) bits.
+ //
+ // The test/data/peacock.progressive.jpeg file has 10 scans:
+ // 1. Ss = 0 Se = 0 Ah = 0 Al = 1 3 components (Y, Cb, Cr)
+ // 2. Ss = 1 Se = 5 Ah = 0 Al = 2 1 component (Y)
+ // 3. Ss = 1 Se = 63 Ah = 0 Al = 1 1 component (Cr)
+ // 4. Ss = 1 Se = 63 Ah = 0 Al = 1 1 component (Cb)
+ // 5. Ss = 6 Se = 63 Ah = 0 Al = 2 1 component (Y)
+ // 6. Ss = 1 Se = 63 Ah = 2 Al = 1 1 component (Y)
+ // 7. Ss = 0 Se = 0 Ah = 1 Al = 0 3 components (Y, Cb, Cr)
+ // 8. Ss = 1 Se = 63 Ah = 1 Al = 0 1 component (Cr)
+ // 9. Ss = 1 Se = 63 Ah = 1 Al = 0 1 component (Cb)
+ // 10. Ss = 1 Se = 63 Ah = 1 Al = 0 1 component (Y)
+ //
+ // The first scan holds the high 7 bits of all components' DC
+ // coefficients.
+ //
+ // The second scan holds the high 6 bits of the 1 ..= 5 AC coefficients
+ // of the Y component.
+ //
+ // The third and fourth scan give the high 7 bits of all of the AC
+ // coefficients of the Cr and Cb components.
+ //
+ // The fifth scan is like the second scan, but for the Y component's
+ // remaining AC coefficients.
+ //
+ // The sixth scan holds the second-least significant bit for the Y
+ // component's AC coefficients.
+ //
+ // The seventh scan holds the least significant bit for all components'
+ // DC coefficients.
+ //
+ // The last three scans hold the least significant bit for components'
+ // AC coefficients.
scan_ss : base.u8[..= 63],
scan_se : base.u8[..= 63],
- scan_ah : base.u8[..= 13],
+ scan_ah : base.u8[..= 14],
scan_al : base.u8[..= 13],
scan_width_in_mcus : base.u32[..= 0x2000],
@@ -390,6 +446,11 @@
var upper_bound : base.u32[..= 0x1_0008]
+ var wh0 : base.u64[..= 0x1_0010_0040] // 0x1_0008 * 0x1_0008.
+ var wh1 : base.u64[..= 0x1_0010_0040] // 0x1_0008 * 0x1_0008.
+ var wh2 : base.u64[..= 0x1_0010_0040] // 0x1_0008 * 0x1_0008.
+ var wh3 : base.u64[..= 0x1_0010_0040] // 0x1_0008 * 0x1_0008.
+
if this.payload_length < 6 {
return "#bad SOF marker"
}
@@ -534,15 +595,16 @@
this.components_workbuf_heights[3] = upper_bound.min(no_more_than:
8 * this.height_in_mcus * (this.components_v[3] as base.u32))
+ wh0 = (this.components_workbuf_widths[0] as base.u64) * (this.components_workbuf_heights[0] as base.u64)
+ wh1 = (this.components_workbuf_widths[1] as base.u64) * (this.components_workbuf_heights[1] as base.u64)
+ wh2 = (this.components_workbuf_widths[2] as base.u64) * (this.components_workbuf_heights[2] as base.u64)
+ wh3 = (this.components_workbuf_widths[3] as base.u64) * (this.components_workbuf_heights[3] as base.u64)
+
this.components_workbuf_offsets[0] = 0
- this.components_workbuf_offsets[1] = this.components_workbuf_offsets[0] +
- ((this.components_workbuf_widths[0] as base.u64) * (this.components_workbuf_heights[0] as base.u64))
- this.components_workbuf_offsets[2] = this.components_workbuf_offsets[1] +
- ((this.components_workbuf_widths[1] as base.u64) * (this.components_workbuf_heights[1] as base.u64))
- this.components_workbuf_offsets[3] = this.components_workbuf_offsets[2] +
- ((this.components_workbuf_widths[2] as base.u64) * (this.components_workbuf_heights[2] as base.u64))
- this.components_workbuf_offsets[4] = this.components_workbuf_offsets[3] +
- ((this.components_workbuf_widths[3] as base.u64) * (this.components_workbuf_heights[3] as base.u64))
+ this.components_workbuf_offsets[1] = this.components_workbuf_offsets[0] + wh0
+ this.components_workbuf_offsets[2] = this.components_workbuf_offsets[1] + wh1
+ this.components_workbuf_offsets[3] = this.components_workbuf_offsets[2] + wh2
+ this.components_workbuf_offsets[4] = this.components_workbuf_offsets[3] + wh3
}
pub func decoder.decode_frame_config?(dst: nptr base.frame_config, src: base.io_reader) {
@@ -1147,8 +1209,62 @@
}
}
- if (not this.seen_dht[0 | this.scan_comps_td[i]]) or
- (not this.seen_dht[4 | this.scan_comps_ta[i]]) {
+ i += 1
+ } endwhile
+
+ if this.sof_marker < 0xC2 {
+ // At this point, for sequential (not progressive) JPEGs, we should
+ // check that (Ss, Se, Ah, Al) is (0, 63, 0, 0) but libjpeg treats
+ // otherwise as a warning (JWRN_NOT_SEQUENTIAL), not an error.
+ args.src.skip_u32?(n: 3)
+ this.scan_ss = 0
+ this.scan_se = 63
+ this.scan_ah = 0
+ this.scan_al = 0
+
+ } else {
+ c = args.src.read_u8?()
+ if c > 63 {
+ return "#bad SOS marker"
+ }
+ this.scan_ss = c
+
+ c = args.src.read_u8?()
+ if (c > 63) or (c < this.scan_ss) {
+ return "#bad SOS marker"
+ }
+ this.scan_se = c
+
+ c = args.src.read_u8?()
+ if ((c >> 4) > 14) or ((c & 0x0F) > 13) {
+ return "#bad SOS marker"
+ }
+ this.scan_ah = c >> 4
+ this.scan_al = c & 0x0F
+ if this.scan_ah > 0 {
+ if (this.scan_ah - 1) <> this.scan_al {
+ return "#bad SOS marker"
+ }
+ }
+
+ if this.scan_ss == 0 {
+ // Progressive DC scans can have only one spectral element.
+ if this.scan_se <> 0 {
+ return "#bad SOS marker"
+ }
+ } else {
+ // Progressive AC scans can have only one component.
+ if this.scan_num_components <> 1 {
+ return "#bad SOS marker"
+ }
+ }
+ }
+
+ i = 0
+ while i < this.scan_num_components {
+ assert i < 4 via "a < b: a < c; c <= b"(c: this.scan_num_components)
+ if ((this.scan_ss == 0) and (not this.seen_dht[0 | this.scan_comps_td[i]])) or
+ ((this.scan_se <> 0) and (not this.seen_dht[4 | this.scan_comps_ta[i]])) {
// TODO: while not required by the spec, we could fall back to
// implicit tables? See section K.3 "Typical Huffman tables for
// 8-bit precision luminance and chrominance" and
@@ -1159,29 +1275,6 @@
i += 1
} endwhile
- c = args.src.read_u8?()
- if c > 63 {
- return "#bad SOS marker"
- }
- this.scan_ss = c
-
- c = args.src.read_u8?()
- if (c > 63) or (c < this.scan_ss) {
- return "#bad SOS marker"
- }
- this.scan_se = c
-
- c = args.src.read_u8?()
- if ((c >> 4) > 13) or ((c & 0x0F) > 13) {
- return "#bad SOS marker"
- }
- this.scan_ah = c >> 4
- this.scan_al = c & 0x0F
-
- // At this point, for sequential (not progressive) JPEGs, we should check
- // that (Ss, Se, Ah, Al) is (0, 63, 0, 0) but libjpeg treats otherwise as a
- // warning (JWRN_NOT_SEQUENTIAL), not an error.
-
this.scan_width_in_mcus = this.width_in_mcus
this.scan_height_in_mcus = this.height_in_mcus
diff --git a/test/nia-checksums-of-data.txt b/test/nia-checksums-of-data.txt
index 793d25b..ea00b59 100644
--- a/test/nia-checksums-of-data.txt
+++ b/test/nia-checksums-of-data.txt
@@ -85,7 +85,7 @@
d49bab2d test/data/peacock.grayscale.jpeg
d42a13cd test/data/peacock.optimize.jpeg
bdf8cc70 test/data/peacock.ppm
-9154cd54 test/data/peacock.progressive.jpeg
+db9b1efa test/data/peacock.progressive.jpeg
951676cc test/data/peacock.q30.jpeg
56835223 test/data/peacock.q99.jpeg
1543f677 test/data/peacock.s-weird.jpeg
